"Basically... porn is everywhere," says a new report from the Children's Commissioner. We try to find out just how much – and what the information we do have says about the UK's habits

• Read analysis of the report from Alexandra Topping
• More data journalism and data visualisations from the Guardian

Unsurprisingly, on the Datablog we often write articles about data when we have data. But some topics, like pornography, aren't conducive to statistical analysis, no matter how important many claim they are.

Despite these challenges, a report released today has sought to assess children and young people's exposure to pornography and understand its impact. Led by Middlesex University and commissioned by the Children's Commissioner, this was a rapid evidence assessment - completed in the space of just three months as part of a much larger ongoing inquiry into child sexual exploitation.

The report found that a "significant proportion of children and young people are exposed to or access pornography", and that this is linked to "unrealistic attitudes about sex" as well as "less progressive gender role attitudes (e.g. male dominance and female submission)".

Though the report makes these and other important conclusions, you'll notice that numbers are conspicuously absent in its language. One reason is that its findings were not based on primary research but a literature review that began with 41,000 identified sources and concluded by using 276 of those that were deemed relevant.

Several of the articles in the references are however quite dated - some published as far back as 1980. That doesn't necessarily mean that the findings are irrelevant. Rather, it shows just how difficult it is to analyse an entertainment activity/hobby/addiction (delete as appropriate) that is as prevalent as it is provocative - or at least we think.

In fact, for a phenomenon that is believed to be so widespread and so regularly features in debates about the state of British society, there is virtually no accurate data on pornography.

In February of this year, I contacted academics that conduct studies on pornography (though many of these look at its impact, rather than its scale) as well as 'industry experts'. One of those was someone working at Erotic Trade Only, which describes itself as "UK's leading adult industry magazine".

I didn't get very far. The industry expert replied "there are no figures, unfortunately, and with the industry continually changing its delivery vehicles and routes to market that is unlikely to change anytime soon".

The academic meanwhile pointed out, "much of what's out there is either self-reported by the industry or by its opponents, neither of which is particularly reliable". That's not even to mention that while a precise definition of 'pornography' remains elusive, so too do efforts to define where the boundaries of its industry stop and where they begin.

So what can be said? Well, like shopping, dating and programme viewing, the proportion of pornography online is growing compared to that which is offline. Maybe then, it's useful to look at some trends on Google. Trends like, for instance, the frequency of porn as a search term which, as the interactive graph below demonstrates, is becoming more common.

This, as the next interactive shows, is a trend which is quite equally spread across the country. England tops the list for online searches, Scotland has 97% the amount England does, Wales 87% and residents of Northern Ireland produce 3/4 the amount of web searches for the term 'porn' that England does.

But since Google Trends doesn't show absolute values, we're still no closer to understanding the scale of porn or its place in British cultural life relative to other trends. Well, what about if we were to use data on the most Googled terms in the UK in 2012 (Euro 2012 tops the list) and compare it to searches for 'porn'?

It appears that even at the height of football madness in June, porn was by far a more interesting topic for those in the UK to type into a search engine. All of which suggests that researchers weren't too inaccurate in titling today's report 'Basically, porn is everywhere'.

Obviously, this approach is far from methodologically watertight. Do you have any suggestions about ways to collect accurate statistics on the prevalence of pornography? Do you know of any reliable sources about its scale in the UK? Share your views, either by posting a comment below or by contacting us via Twitter on @GuardianData or @MonaChalabi.

More open data

Data journalism and data visualisations from the Guardian

• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Children
• Pornography
• Family

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

How likely are you to see a piece of art in a London gallery created by a woman? An art audit by the East London Fawcett Group has attempted to find out
• Get the data
• More data journalism and data visualisations from the Guardian

An audit of more than 100 commercial galleries in London has found that only 5% represent an equal number of male and female artists.

East London Fawcett's (ELF) art audit also found that not a single woman appeared on the top 100 auction performances list in 2012. The audit which looked at works from April 2012 – April 2013 gathered data on 134 commercial galleries in London, which collectively represent 3,163 artists.

Of this total, just 31% of the represented artists were women, with 78% of the galleries representing more men than women. Kira Cochrane writes today:

Here's a teaser. How many women artists featured in the top 100 auction sales, ranked by price, last year? Gemma Rolls-Bentley, an independent curator, decided to find out.

One day, not long ago, she sat down with the 2012 list, "and spent a couple of hours writing M next to the artists. I got to the end and there wasn't a single F." Some of those artists were alive, some were dead, all were highly valued - clearly considered "great" or "genius" - and all were men.

ELF, the East London branch of the Fawcett Society, also turned their attention to gender representation in solo shows featured in the exhibition programmes of 29 non-commercial galleries in London. Nearly a third of the galleries presented no female solo shows during this period and only one of the gallery programmes featured all female shows.

Public art also came under scrutiny from the ELF audit. Of the 386 public works of art that were recorded in Westminster and the City of London, a mere 8% were created by female artists. That may not come as much of of a surprise if you take into account that a large proportion of the pieces of art date back many years.

So if we look at the modern day, do female artists fare better? A quarter of the artists selected for the Fourth Plinth, situated in the northwest corner of Trafalgar Square, were female, as Kira Cochrane writes today "far from brilliant, but much better than those other statistics for public art".

Frieze Art Fair, an annual showcase of leading international artists, provided some interesting results. 27.5% of the artists represented at the art fair in 2012 were women. The results are a reflection of a survey that took in 3,441 artists across 135 international galleries that were represented in the commercial section of Frieze Art Fair 2012.

However, 23.3% of solo exhibitions hosted by commercial galleries in the capital during Frieze week presented female artists – an increase on the 11.6% figure that Laura McLean- Ferris found in 2008 when she conducted a similar survey.

Gemma Rolls-Bentley, arts director at ELF, is optimistic despite the gender gap displayed by the results:

The ELF art audit results provide statistical evidence that gender inequality still persists in London's art world. However, these results also demonstrate that significant positive progress has and is being made.

By raising awareness of the challenges specific to female artists, we hope that the campaign will widen the dialogue around this issue and that as a result the gender balance will continue to improve. The art audit's message is one of optimism.

Campaign group, UK Feminista, published results in 2010 of a similar piece of research looking at gender inequalty in the art world. They found that 83% of the artists in the Tate Modern and 70% of the artists in the Saatchi Gallery were male.

But the gender gap is the reverse when you look at university stats. In her Datablog piece examining the gender gap at universities by institution and subject, Rebecca Ratcliffe found that 61.7% of the undergraduate creative arts and design intake in UK universities in 2011-12 was female. So why are so few female artists being represented in art galleries? We'd love to hear your views in the comments below.

Download the data

• DATA: download the full spreadsheet

More data

More data journalism and data visualisations from the Guardian

• Follow us on Twitter
• Like us on Facebook

• London
• Art
• Exhibitions
• Frieze art fair
• Women
• Gender
• Equality
• Feminism

Ami Sedghi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

Since 2011, net migration has been on the decline due to falling numbers of immigrants. What are the other key trends behind these often controversial statistics?

• Get the data
• More from the Datablog on immigration
• More data journalism and data visualisations from the Guardian

It's that time of year again: the release of migration statistics. Many will be keen to inspect how close these numbers come to the Conservative's target to reduce net migration to 100,000 by 2015 when they will again face the vote.

The latest numbers from the Office for National Statistics show that net migration was 153,000 in the year ending September 2012, compared to 242,000 the previous year.

Alan Travis has more on the story here, including this comment from the immigration minister, Mark Harper:

The figures show we have cut out abuse while encouraging the brightest and best migrants who contribute to economic growth, with a 5% increase in the number of sponsored student visa applications for our world-class universities, and a 5% increase in the number of visas issued to skilled workers.

Latest totals

Though the data for the twelve months to September 2012 is still provisional, it suggests that half a million people immigrated to the UK. This represented a 14% reduction from 581,000 immigrants (or 'inflow' as it's named in the data).

Long-term emigration meanwhile is rising - up 2% from 339,000 in the year ending September 2011.

Though immigration and emigration have moved in opposite directions over the past year, the changes have not been enough to offset one another meaning that net migration remains a positive value.

Reasons for coming

A critical piece of information for policymakers - wherever they sit on the political spectrum - is the reason given by those who have decided to enter or leave the UK. Here, trends are just as visible as elsewhere.

Formal study has been the most common reason given by those immigrating, followed by a work-related motivation. Almost half (190,000) of long-term migrants state study as their reason for coming, though these individuals often receive less attention than the 62,000 who come to the UK to accompany or join a family member already here.

Also, often overlooked is the fact that the majority of those who state work as their reason for coming (175,000) are also able to state that they have a definite job. A smaller fraction, 38%, come to the UK in search of employment.

58% of those leaving the UK cite work as a reason for doing so - of these, 64% have a definite job waiting for them in their destination of choice, the remainder state that they are heading off in search of work.

Changes in motivation appear to coincide with the financial crisis - more people leaving the UK cited work as a reason for their decision after 2007. Similarly, 2007 was the first year in which more immigrants cited study rather than work as a reason for coming - a trend which has continued ever since.

Citizenship trends

Finally, who exactly is arriving and (probably a less controversial question) where are people leaving the UK going to? Well, the Office for National Statistics summarise these numbers using the following headings:

• British
• EU
• EU 15 (EU countries as constituted between 1 January 1995 and 1 May 2004)
• EU 8 (eight Central and Eastern European countries that acceded to the EU on 1 May 2004)
• All non-EU - which is comprised of
• Old commonwealth
• New commonwealth
• Other foreign

When the numbers are broken down by citizenship, some of the most striking trends are to be seen among non-British citizens. For example, net-migration of non-British citizens has fallen by 25% from 303,000 in 2011 to 228,000 in 2012. Net-migration of EU citizens remained more stable, falling by 12% to 66,000 in 2012 compared to the previous year.

Non-EU destinations remain slightly more appealing to those leaving the UK - 78,000 headed to EU countries compared to 104,000 leaving to places outside the European Union.

Below are biannual and, where available, quarterly figures for inward and outward long-term flows as well as net migration. What can you do with the data?

Download the data

• DATA: download the full spreadsheet

More open data

Data journalism and data visualisations from the Guardian

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Immigration and asylum
• Migration
• Office for National Statistics

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

A decade of global data attempts to analyse the details of bullying. But what can the figures really tell us about an issue that is so difficult to record?
• Get the data
• More data journalism and data visualisations from the Guardian

The evolution of social media and mobile communication may have made it easier than ever for young people to share but they also create an environment that can make bullying "inescapable and even more threatening than ever before" according to a new report by Child Helpline International (CHI).

CHI, a network of government and civil society organisations, operates 173 child helplines in over 142 countries and in the past 10 years has collated a database of more than 126m contacts by children and adults on behalf of young people from its member helplines.

The 126m refers to the number of conversations that have taken place between a child or young person and a counsellor of a child helpline somewhere in the world, on any subject a child or young person wanted to talk about. The database has collated data through any form of communication used by child helplines including telephone, chat, SMS, message boards, walk-in centres and outreach activities.

Of the 126m, nearly 4m have been about abuse and violence, including categories such as bullying, emotional abuse, physical abuse, sexual abuse and neglect. And since the CHI started collecting data on cyberbullying in 2011, more than 27,000 contacts have been recorded on this subject.

On average, every child helpline in the world receives nine contacts from children and young people per day who are suffering the effects of bullying, according to CHI.

Of course the results of this report don't tell the whole story, for every child that seeks advice by contacting a helpline, there are many more that either do not have the access, confidence or privacy to do the same.

As a result, gathering data on the number of children suffering from bullying has never been simple, but the CHI's analysis helps give an insight into a global problem affecting many.

NSPCC statistics on bullying collated from government reports and research suggest that almost half of children and young people have been bullied at school at some point in their lives. The NSPCC also report that 38% of young people have been affected by cyberbullying.

Figures from a 2011 report by the Department of Education (DfE) also show that girls are twice as likely to experience persistent cyberbullying than boys.

This trend was also apparent in CHI's analysis - the number of girls contacting them about cyberbullying was slightly higher than boys, although 90% of those contacting child helplines "hesitated to disclose their gender to protect their identity and maintain their anonymity after having suffered online abuse".
The overall proportion that were not willing disclose their gender for recording purposes was 71%.

Ofcom research, published in 2008, showed that almost half of children aged 8-17 who use the internet had set up their own profile on a social networking site. The Ofcom research also reported the following observation:

It also appears likely that when children receive hostile, bullying or hateful messages, they are generally ill-equipped to respond appropriately or to cope with the emotional upset this causes

So what else does the release by CHI show? Well, the number of contacts received in 2012 was more than double those received in 2006, but as CHI note, the rise in contacts could also be associated with growing awareness of bullying amongst children.

Bullying can take many forms but analysis on information gathered since 2011 has highlighted four major categories; emotional, physical, exposure and theft.

Almost half of the contacts on bullying could be be categorised as emotional bullying and nearly a quarter as physical abuse. Instances where young people have been either exposed to bullying as a witness or have had belongings stolen accounted for 12.5% of contacts each.

Emotional bullying and theft were the most common types of bullying reported by girls, whereas boys were most likely to contact a helpline due to physical bullying, exposure or theft.

Analysis of contacts made with child helplines show that nine out of ten cases of bullying take place at school, although this fact may not come as a surprise, the breakdown of who the bullies are makes for interesting reading. Over a third of indicated perpetrators were adults and globally, teachers were responsible for more than 23% of bullying; more than 14% by male teachers, 7% by female teachers and 2% gender not known.

Regional breakdown of the data also provides some fascinating insights into how differences in culture and community affect the figures. Whilst in Europe around 4% of contacts about bullying involved a teacher, this figure reaches 37% in Africa.

But as we know bullying can be much more complex than the figures can possibly show. Differences in culture, attitudes and laws against corporal punishment can help to explain the vast differences in percentages.

More children and young people in Europe contacted child helplines on the issue of bullying than any other region. More than half a million contacts have been made in Europe over the past 10 years. Asia Pacific follows with almost 135,000 contacts, America and the Carribean with nearly 100,000, Africa with 55,000 and lastly the Middle East and North Africa with 8,856. As discussed above, culture and socioeconomic factors (the likelihood that a family will even have a phone or access to a counsellor) are likely to influence these geographic trends.

In all regions except the Middle East and North Africa, the majority of contacts on bullying were from girls. In the Middle East and North Africa however, 55% of contacts were made by boys.

Bullying can be a problem for teachers as well as students as a NASTUWT survey published last April demonstrated. 42% of those teachers filling out the survey said they had received an insulting comment, allegation of inappropriate behaviour with a pupil, comment on their performance or other comment posted online or on a social networking site.

Chris Keates, NASUWT General Secretary said at the time of release that:

A significant minority of our members are being abused by their pupils and that in too many cases the action taken does not reflect the seriousness of the abuse

CHI acknowledge that as with any, empirical study, there are certain strengths and weaknesses to the release. So here are some things to consider when looking at the data:

• The numbers in the Excel files might slightly differ from the data in the thematic briefing paper. This is due to the fact that CHI are currently still working on their data collection for 2012 and at the moment, are continuously updating the database. They assure us that "Overall, the proportions will not affected much".

• The category 'Unknown' is not included in the data on the involvement of peers and teachers as for the majority of contacts, the status of the perpetrators is not known

• In the case of gender disaggregated data, the unknown category is also been left out for similar reasons as above.

How useful is data on bullying? Did CHI's analysis tell you anything you didn't know before? Discuss the results in the comments thread below.

Download the data

• DATA: download the full spreadsheet

More data

More data journalism and data visualisations from the Guardian

• Follow us on Twitter
• Like us on Facebook

• Children
• Bullying
• Cyberbullying
• Social networking

Ami Sedghi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

The New Scientist has mapped violence in Syria, illustrating how the conflict has evolved in scale and severity since hostilities began in early 2011

John Burn-Murdoch

Charting every result from the 1,500-match and 27-year era of Sir Alex Ferguson's reign at Manchester United

Chris Fenn

The Rendition Project, a collaboration between UK academics and the NGO Reprieve, has produced one of the most detailed and illuminating research projects shedding light on the CIA's extraordinary rendition project to date. Here's how to use it.

• See The Rendition Project interactive here

The Rendition Project, run by UK academics, has collaborated with the NGO Reprieve to produce one of the most detailedand illuminating research projects shedding light on the CIA's extraordinary rendition project to date.

In a single interactive graphic, it shows in great detail the data behind every confirmed and suspected rendition flight, and then – as it's also intended as a tool to fuel further research and digging – a huge number of other flights of the planes linked to rendition. In total, the data powering the graphic runs to more than 11,000 lines.

Of course, that means that the graphic's complex, and so we've provided a guide on how to read and interpret it below.

A key caveat is that not every flight contained within the interactive is tied to rendition: some are suspected rendition flights, others are simply flights from planes with tail numbers that were used on suspected rendition flights.

It's also important to note that just because a particular company owned or operating a plane believed to have been involved in rendition, it does not necessarily follow that the company itself was involved or even aware of those activities. In some cases, it's unclear whether the airline companies would have been aware of the purpose of the flights.

A wealth of supporting data and research – including original documents – has been published directly on The Rendition Project's website.

Now, here's how to get the most from the interactive:

Picking what to look at

By default, the graphic shows a huge tangle of different flight routes – it's displaying information on the 1,500 or so flights marked as significant within the data: the ones with some suspected involvement in rendition (those doing advanced research can toggle this off using the "key circuits only" drop-down menu).

The graphic's easiest to use if this is narrowed down. The graphic is broken down into "circuits" of flights: a full trip made up of several different legs. The screenshot used to illustrate this post represents a round-the-world circuit made up of a number of different airport-to-airport trips.

Circuits can include original journeys from America, R&R stops in the Caribbean, refuelling stops, and the central rendition journeys themselves.

The menu on the left-hand side of the graphic gives a range of ways the information can be narrowed down: trips which only take in certain airports can be picked, or particular companies, or particular individuals known to have been targets of rendition. The date range can also be selected using the sliding toggles.

Hitting the large "SEARCH" button at the bottom-left will then update the map with the new settings.

What the different colours mean

Different individual flights are colour-coded by their significance.

The simplest flights are marked in grey. These are legs of the flights where the researchers had no reason to believe there was any detainee aboard the aircraft. These mark refuelling stops, planes getting into position, R&R stops, or similar.

At the other end of the scale, strong red lines mark a flight designated a "rendition flight". These are flights where the researchers are as near as possible as investigators on these topics can be to certain that a detainee – often a named detainee – was aboard the plane. These are backed by a wealth of evidence.

Paler red lines mark "highly suspicious" or "suspicious" flights – one where there is evidence – often strong – to believe a detainee was aboard a given flight, but where the researchers are not quite so confident.

Some of the "suspicious" flights have been flagged because of very similar routes or timings to flights tied to rendition, rather than specific evidence on that particular flight.

The blue lines are perhaps the most interesting, as they shed light on the lengths US authorities went to in attempts to hide rendition flights. Blue designates "dummy" flight plans: routes handed in to air traffic authorities, and then never flown.

Instead, the planes flew to entirely different airfields – often in different countries altogether – typically with an unwilling passenger on board.

Getting the evidence

There are some written details on any flights shown in the map window in the table below it in the graphic. Any flights with a red square in this table – which should include any flights with confirmed or suspected renditions – have substantial further information available.

Hovering over this red square will supply some basic information on the flight, along with a range of links to further information (where available) on that particular circuit, the planes, or the detainees, directly from The Rendition Project's website.

Once you're looking at just a single circuit on the map, the table below the map includes information on each individual flight on that trip.

Where it's available, the researchers have included direct links to the source material, including invoices and court records, supporting their claims.

Further queries, research, and more

The team behind the graphic intend for it to be used to dig out further evidence of any more, still unknown, rendition flights – or to shed more light on those already uncovered.

As such, they've provided a huge amount more information on the graphic, the data collection methods, advanced functionality and more directly at their website.

We're also keen to see what people have found – or want to know – from the graphic. Feel free to let us know in the comments below, on Twitter @GuardianData, or if you'd prefer, confidentially by email to james.ball@guardian.co.uk

• Rendition
• CIA
• US constitution and civil liberties

James Ball
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

The Rendition Project has spent three years creating an interactive guide to CIA rendition flights of terrorist suspects, containing more than 11,000 rows of data

James Ball

It's not just UK homeowners that are considering downsizing, one of the country's biggest landowners is doing it too: the government. We look at how the state estate has changed since 2011

Get the data
More data journalism and data visualisations from the Guardian

The government has been criticised in the past for its inefficient use of the buildings it owns. From the plans for small businesses to take over the disused premises to suggestions that they be turned over for community use, there has been pressure from a number of quarters that the government could save space and money.

It appears that they've responded to that pressure. Data released by the Cabinet Office today shows that the government's estate has shrunk 10% from 10.3m square metres in 2011 to 9.2m square metres in January of this year.

The data unfortunately does not include information on who these properties were sold to (or, if they weren't owned, who they are no longer being rented or leased from) what they are now being used for or the amount of money spent/saved per building.

It does however show that, taken together, 190 government buildings split between 31 different departments or organisations shrunk by 1,081,535 square metres between 2011 and 2013.

That does not mean that every government building shrunk. In fact, 39 of those included in the data actually increased in size and 31 didn't change at all.

The biggest changes were:

HM Revenue and Customs shaved off a whopping 205,000 square metres from its estate - cutting it down to a mere 1.1 million square metres
The next biggest shrinkage was for the Ministry of Justice's National Offender Management Service (NOMS) which lost 117,000 square metres
Her Majesty's Court Service by contrast witnessed the largest growth (42,000 square metres) closely followed by the British Transport Police Authority who acquired new premises 41,000 square metres in size

The State of the Estate report also looked at other features of the government estate. It found that 764 buildings were constructed after 1990 out of the 2,719 government building that had their age profiled. 182 of those buildings date back to pre-1900.

The report also looks at how sustainable the various government buildings are and finds that most are performing well in reducing greenhouse gas emissions, water and waste. And just like responsible homebuyers, the report looks at the energy performance of new government acquisitions. Topping the list are the new Ministry of Justice buildings in Caernarfon and Llandrindod Wells.

The largest vacant public buildings were to be found in the North West and the South West where 41,00 and 40,000 square metres respectively were not in use.

Though there isn't a breakdown per building, the report does show which government departments and organisations have the largest annual running costs. At £604m per year, it's perhaps unsurprising that the department dealing with prisons tops the bill - the Ministry of Justice.

Speaking about the changes, Francis Maude, Minister for the Cabinet Office said:

We are pushing forward our ambitious programme to sell property we no longer use and get out of expensive rentals.

Since the last general election we have saved the taxpayer over a £1 billion and made space available in desirable central locations for redevelopment. This is not only about changing the way we work but generating an economic boost.

The changes over the past two years are part of the Government Property Unit strategy, the next stage of which concentrates on putting the existing space to better use.

What do you think about these changes? Do they reflect a sensible rationalisation of otherwise inefficient resources? Or is downsizing an inevitable consequence of public sector job cuts? Share your views via Twitter @MonaChalabi or @GuardianData or by posting a comment below.

Download the data

• DATA: download the full spreadsheet

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Government data

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

What do emptier waters look like? This web aquarium shows declining fish populations over the past 100 years - and it uses more than 200 datasets to do it. We recommend that you closely analyse the data showing that the population of big fish has been decimated while small fish are now overly abundant. Or else you can leave it on your screen as a digital pet and a grim modern Tamagotchi.

Mona Chalabi

Heterosexual civil partnerships are on the cards for the UK, thanks to a tabled amendment to government plans on gay marriage. Is there any evidence as to how many people want them?

Read the reality check from Shiv Malik here
Get the data
More data journalism from the Guardian

When your stance on a subject risks you being branded as homophobic, disrespectful of religion, out of touch or anti-establishment it might be better to argue your case on the basis of cost. And with a subject as sensitive as gay marriage on the table, that's exactly the strategy many MPs appear to be adopting.

Or at least indirectly. In fact, the current debate between MPs is about the potential price tag if heterosexual couples were also to be granted civil partnership rights but many suggest that, if passed, the amendment could derail the gay marriage bill.

The estimated costs for amending the bill have varied between £90m to £4bn - leading critics such as the Conservative MP Tim Loughton to brand the numbers as "back of fag packet scaremongering". While Shiv Malik is taking a look at how the numbers stack up on the reality check blog, we're considering the number of people the legislation is likely to affect.

Peter Tatchell, sponsor of Equal Love, a group campaigning in favour of both same-sex civil marriage and opposite-sex civil partnerships, said "you can't put a price on equality. When it comes to equal rights, cost should not be a factor". He added, "if civil partnerships were made available to heterosexual couples in the UK there would probably be a similar significant take up".

We're not so sure. For one thing, there's a difference between short-term and long-term demand - as demonstrated by the number of civil partnerships in the UK which fell quite steadily from 16,106 in 2006 to just 6,795 in 2011.

The Datablog covered all the numbers the last time that the Office for National Statistics released data on civil partnerships in July 2012. Here are some of the main statistics that came out of our analysis then (you can find these, and more, in the data link below)

The number of people entering a civil partnerships (106,834) was five times the number initially predicted
The average age for entering a civil partnership was just over 40 for men and 38 for women
1,768 civil partnerships were dissolved between 2007 and 2011

Given that heterosexual couples have the option of marriage (which currently offers a preferable pension to widowed partners than a civil partnership) it seems unlikely that heterosexual civil partnerships will see the same intial uptake.

When the Government Equalities Office looked instead to what had happened in other countries such as Argentina, Canada or Iceland where same-sex marriage has been introduced they found that there was "insufficient evidence" on demand. With one exception: the Netherlands.

The Netherlands is also a critical case study for the proposed amendment since it has followed a path similar to the one projected for the UK - same sex couples were allowed to enter into registered partnerships from 1998 and in 2001 same sex couples could enter into civil marriages. Since 2001, registered partnerships and civil marriages have been open to same sex and opposite sex couples and they are able to convert between the two.

As data from the Netherlands shows, the number of partnership registrations between men and women did increase. But the numbers weren't huge - from 2,847 in 2001 to 7,774 in 2002 (compared to 83,970 marriages between men and women in the same year).

In 2009, Tom Freeman and Katherine Doyle began a legal challenge after applying for a civil partnership and being refused. The pair had the backing of Equal Love which, according to its website, also receives the support of MPs and MEPs from the Labour, Conservative, Green and Liberal Democrat parties.

You can add your voice to this debate either via Twitter to @MonaChalabi or @GuardianData or by starting a discussion below.

Download the data

• DATA: download the full spreadsheet

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter

• Gay marriage
• Civil partnerships

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

Velocity, not volume is increasingly what determines the hardware and software needs of data-processing organisations
• More from the Guardian's series on big data

Critics of big data are picking holes in its validity as a concept, but there is a problem with their arguments around data volume - it is speed, not size, that defines big data in 2013.

Big data is among the computing neologisms du jour, and a technology conference in 2013 is rarely considered complete without a smattering of uses, typically accompanied by further volume-related qualifiers (tsunamis of big data being by far the worst offender I have encountered - other suggestions welcome).

Despite having been in use for a few years now, settling on just what is meant by big data appears to be a complex task. As is their wont, various computing gurus (that one isn't confined to tech circles) have come up with initialisms to summarise what they see as its key constituent parts.

The 'four Vs' definition is probably the most widely recognised - the letters standing for volume, velocity, variety and variability - and from a technical perspective, this is actually a reasonable effort, but a number of otherwise excellent articles currently making the rounds deal only with the first V.

A healthy dose of scepticism is a must when dealing with emergent terms in the technology sector, but in this particular case, commentators would do well to delve a little deeper before setting out to dismantle big data as a concept.

Last month we re-posted an interesting and well-constructed argument that 'small data' - or data of the volumes most regular analysts, researchers and statisticians are used to dealing with - is actually both more relevant and more useful to the vast majority of organisations than its big cousin.

More recently, I read a well-researched article on just how infrequently the world's data powerhouses - citing Facebook and Yahoo! - actually carry out an individual piece of analysis on data that would not fit onto a laptop or desktop machine you could pick up from your local electronics retailer.

The points made in both of these articles are eloquently put and there no obvious holes to be found in the arguments' logic. The problem is, both authors dismiss big data on the grounds of volume alone, ignoring the fact that it is speed, not size that is increasingly driving desire for software and hardware improvements at data-processing organisations.

The need for genuine real-time results is integral to ever more analytics use cases. There are, of course, industries where gathering, analysing and reacting to data is nothing new - take high frequency trading, for example. But the list is growing, with information security, marketing and telecommunications just three examples of sectors where speed, more than volume, has been identified as a limiting factor.

Last week Paul Maritz, CEO of EMC Pivotal, described a marketing paradise in which customers in a store are tracked and served offers while they shop - insights put into action instantly, rather than retroactively, as we currently see with deals offered at the point of sale.

Leaving aside for now the numerous privacy and intrusion questions that arise from such a scenario, the message here is that data-centric companies seeking to gain a competitive edge have marked out velocity as the new battleground.

In fact it is just as fallacious to consider speed in isolation from volume as it is to do the reverse - the pair form two sides of a speed-data-time triangle. As the values for data and time tend towards infinity and zero respectively, the software and hardware requirements ramp up.

In short, once you really consider the technical challenges facing CTOs, data scientists and others embedded in this field, the idea that big data be dismissed as a term because it's not all that big is - however well presented - verging on straw man territory.

Which side of the big data debate do you sit on? Join the discussion in the comments below, or have your say via Twitter to me directly @jburnmurdoch or to the official @GuardianData account.

• Big data
• Computing
• Yahoo
• Google
• Facebook

John Burn-Murdoch
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

A review of England's fire and rescue services has found it could be saving nearly £200 million per year. Firefighters are already claiming that this is nothing more than a cover for cuts. We take a closer look

Get the data
More data journalism and data visualisations from the Guardian

It must be a Friday: a government report was released that seems to spell out good news for everyone. A document titled 'Facing the Future' set out a dramatic drop over the last decade in the number of fires, fatalities, and related incidents across England.

Good news for everyone – except maybe firefighters, as the report's being used to justify substantial proposed cuts and consolidation in the fire and rescue services.

The independent review, commissioned by Brandon Lewis, the fire minister, finds that there has been "a massive reduction in emergency incidents in the last decade" but also addresses the potential accusation of cuts head-on (if in somewhat obtuse language) by adding:

"I am cognisant of the time in which this review is published, a time of austerity which is likely to continue with downward pressure on public expenditure".

Saying that savings of £196m a year are possible for England's fire and rescue services is no small claim – so we've decided to take a look at how that figure is arrived. Is there really that much less to do?

Lower risks?

According to the report, the fire and rescue services are attending 40% fewer incidents. They published the chart below to demonstrate the trend.

When we looked at the annual statistical releases we found the data on fire fatalities that was used to make this graph (page 8).

The 15% drop in all fire fatalities does slightly obscure the fact that fatalities from accidental dwelling fires – the 'chip pan' or 'dropped cigarette' fires of family nightmares – fell somewhat less, by only 9%.

Next, we looked at the 'incidents' data in this graph - which, according to the key findings in the report have declined by 40%. Well, it appears that 'incidents' refer only to 'fires'.

But is there a catch?

But firefighters don't only go out to real fires: when a call comes in, they've no way to know if it's a false alarm or not, and of course firefighters engage in other non-fire services, from aiding in road traffic accidents to (apocryphally) rescuing cats in trees.

Expanding the range of incidents to cover fire, false alarms, road-traffic accidents and non-road traffic accidents then the total rises from 473,412 incidents in England in 2003 to 908,927.

Doing the same for 2012 isn't exactly possible as we only have six months of figures, which total 272,000 for the period of April to September 2012.

So, have incidents still fallen? The answer's a slightly unsatisfactory "probably": there could well be more incidents in the winter months than in the summer. But using a simple estimate of 544,000 for the year leaves an overall drop of around 40% in total incidents, not just fires. So it's quite possible the government has a point.

New risks?

But, then again, they might not. Though it's clear that England's fire and rescue services aren't putting out as many fires, that may not necessarily be reason enough to suggest cutting back.

Between April and September 2012, fire and rescue services attended 69,400 non-fire incidents which often require different skills and equipment.

Some of these, such as rescue of persons, animal assistance incidents and lift releases have declined since - but several of these incident types are up.

Take, for example, the 9,200 incidents of flooding which required the assistance of fire and rescue in England over the space of six months - up 75% from the same period the year before.

With meteorologists suggesting that our more turbulent weather is getting harder to predict, it might not be wise to believe that past risk levels accurately indicate future risk levels.

It's also entirely possible that the preventative work carried out by fire services is a contributor to falling numbers of fires – and so cuts could lead to increases.

Cuts have already begun

Sir Knight's report claims that despite "a massive reduction in emergency incidents in the last decade... no similar significant change in the makeup or cost of the service has taken place".

Fire and rescue teams in England will no doubt be keen to point out that from 2007 to 2012, there was an 8% reduction in fire staff and a 5% reduction overall in the number of fire and rescue personnel.

"A fig leaf"

In response to the review, the Fire Brigades Union published the following statement on their website:

The review of the fire and rescue service by Ken Knight is just a fig leaf for slashing our fire and rescue service to bits. David Cameron has promised to protect front line services. That has been exposed as a lie over the past three years as the fire service has faced the biggest cuts in its history.

Do you think this report highlights the paradox of constant resources and declining need or do you think it has cherry picked the numbers? Share your views by tweeting to @GuardianData or @MonaChalabi, or by posting a comment below.

Download the data

• DATA: download the full spreadsheet

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Firefighters
• Emergency services

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

The Eurovision 2013 final is upon us, but who does the data say will win – and will Bonnie Tyler be totally eclipsed?

• Get the voting data

It's finally here: the eve of the kitschest night of the year: the Eurovision song contest. While for most the fun comes tomorrow – who'll have the strangest accent? Will the hosts be dire? Will anyone actually give the UK any points? – for us at the Datablog the real fun, of course, is in the stats.

So, all week we've done nothing more than work out how to predict who's going to win this year's contest. And we're going to – boldly – set out what we reckon below. But any gambling losses as a result of our predictions are, we're afraid, entirely on your own heads.

We've tried to predict the Eurovision before, in 2011, and didn't do too badly: the eventual winner was in our predicted top three. This year, though, we've got two rival systems – one from our data editor, James, and the other from Margot Huysman.

Prediction one: the cynic's view – James

By now, even infants aren't naïve enough to think the Eurovision Song Contest has anything to do with music. It's all about politics: who likes who, who's in, who's out – and who might cut off the oil supply this winter if they don't get douze points.

Crunching scoring data from the last ten years corroborates the cynics' view (as most things do): voting blocs seem to be pretty real, and points given correlate with points received. We've put all of this voting information in the interactive graphic below. The eastern European voting bloc in particular seems quite strong:

So, what does that mean for the winner? At the extreme, it suggests we could ignore the song entirely, and just look at the voting patterns for the last decade: the countries who score well one year should score pretty well the next (with the song being mere random noise).

That's what we've shown in the table below – which averages scores over the last decade, then removes countries which haven't reached the final for the last five years.

It seems to bode well in particular for Azerbaijan and Russia on Saturday night, but then as the next two top tips haven't even made the final (gulp), the third tip has to be Greece.

But are they really all that popular in the Eurozone right now? And could they afford the hosting bill if they win?

Prediction two: the song matters – Margot

Until 2004, qualification for the Eurovision contest was based on the average points received over the five previous years. However, that year, the system was dropped in favour of semi-finals.

The songs performed in the semi-finals are exactly the same as the ones performed during the final, and apart from a longer running order, all three nights are quite similar. If votes are based on preferences, then the songs that are popular in the semi-finals are popular in the final show as well.

Ever since the institution of the semi-final system, the winner of the competition has been present in the list of top songs in the semis. The only time this has not happened was when Germany won in 2010.

The data looks good for using the semis to predict the result: for the nerds, about 55% of the score in the finals is predicted by the score in the semis. In other words, you're really quite likely to score well in the finals if you do in the semis. So this is a brilliant way of predicting the final!

A slight flaw in this method is that it does not account for countries that are directly qualified for the final, which are France, the UK, Germany, Spain and Italy. However, none of these countries – except, as we said earlier, Germany – have won in the last nine years.

There's maybe a bigger problem, though. Eurovision themselves have also realised the semi-finals help prediction a lot. And so in order to "maintain the suspense going until the last minute", they've hidden the results.

But if you had access to the points, looking at the top scorers in the semi-finals could give you a good indication of who will be in the top three.

This being the Guardian, though, we've come up with a cunning workaround. On Friday morning, we asked people for their top three semi-final acts. More than 1,000 people responded to the unscientific poll (thanks!) – and based on that, expect good things from the Netherlands, Denmark and Greece.

The verdict

So, we have two battling sets of predictions.

Using the semi-finals to predict the finals looks pretty good: it's the richest source of data, it's pretty logical, and the correlation seems to back it up. But there's a big unknown quantity as a result of not having the real figures.

But if this is the system for you, our tips are: the Netherlands (33/1), Denmark (8/11) and Greece (50/1).

If you prefer the old-fashioned "the song doesn't matter" approach, then Azerbaijan (16/1), Russia (16/1) and Greece (50/1) are the picks for you.

Odds taken from oddschecker.com and correct as at 13:30 on Friday. We're not endorsing betting, though.

Alas, only if you're a wildly patriotic (and optimistic) Brit can we recommend rooting for Bonnie Tyler. But good luck with it all the same.

What do you think of our predictions? Got a system of your own? Let us know in the comments below or via Twitter @guardiandata – and if you want to make one from scratch, we've included all the voting data since 1975 in the Google doc below.

Get the data:

DOWNLOAD THE DATA

• Eurovision
• Eurovision 2013
• Bonnie Tyler
• Television

James BallJohn Burn-Murdoch
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

The Datablog is trying to predict the winner of Eurovision 2013 – but we need one more bit of data: who did you think did best in the semi-finals?

The results – and the rest of our predictive data – will be posted on the Datablog on Friday afternoon

• Eurovision 2013
• Eurovision

James Ball
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

5.78 million people in Britain do it, but what is the impact of providing unpaid care? As part of its continuing work after the 2011 census, the Office for National Statistics has taken a look

• Get the data
• More data journalism and data visualisations from the Guardian
• More on UK census: immigrants
• More on UK census: religions

Approximately 9% of men and 12% of women in England and Wales do it, but it's easy for their work to become invisible to policymakers and statisticians: unpaid care.

A new release from the ONS on Thursday has sought to take a closer look at this work, its growth and most of all, the impact on those who provide it.

The report finds young carers face a disproportionate impact on their health. Before taking a look at some of the other trends, it's important to be clear on what the ONS means when it talks about unpaid care:

A person is a provider of unpaid care if they look after or give help or support to family members, friends, neighbours or others because of long-term physical or mental ill health or disability, or problems related to old age. This does not include any activities as part of paid employment.

No distinction is made about whether any care that a person provides is within their own household or outside of the household, so no explicit link can be made about whether the care provided is for a person within the household who has poor general health, or a long-term health problem, or disability.

Age

Those aged 50-64 shouldered the greatest part of the responsibility for unpaid care in England and Wales, and there are more women than men in this category. The report suggests a number of reasons for this - women in their 50s are more likely to leave the labour market to provide care, they retire earlier and the peak in this age group might be because those aged over 65 need care themselves.

Young carers, those aged under 24, make up around 5% of all unpaid carers (around 289,000 people) but - as the following sections consider - may struggle more than other age groups with the responsibility of providing care for free.

Health

Because this data was part of the 2011 census, it's been possible to compare how the health of unpaid carers compares to that of the general population. When asked to rate their health by choosing one of five categories ('very good', 'good', 'fair', 'bad' and 'very bad'), those providing unpaid care were more likely to reply 'not good' than those not providing care. The trend of lower reported health were true across regions, ages and genders.

The difference between those providing 50+ hours per week of unpaid care and those providing none at all (shown below using the black line) was most pronounced for under 24 years of age. Whether male or female, the youngest unpaid carers are almost five times more likely to state they're not in good health than their counterparts who don't provide this service.

Economic position

Though unpaid care is more common among part-time workers, it may come as a surprise just how small the difference is between economically active and the economically inactive. For example, 2.2% of economically inactive women provide 20 to 49 hours unpaid care - for economically active women, that figure only falls to 1.6%.

Unsurprisingly, this correlated with the other factors described here. So the more unpaid care you provide, the more likely you are to state your general health is 'not good' - and nowhere is this trend more noticeable than for those who state their economic position is that of 'student' (many of whom are also likely to be those aged 0-24).

The data also shows that the gender gap is less pronounced for the economically inactive - but as the next section shows, that trend is not noticeable across the board.

Gender gap

Across all regions in England and Wales, women were more likely than men to be the providers of unpaid care. This inequality (see the chart below) has had particularly disadvantaged women wanting to take up work opportunities or remain in employment according to the ONS report.

The gap between men and women narrows slightly in retirement. Surprisingly however, a greater proportion of men than women state that they are 'looking after the home or family', especially when providing more than 50 hours of care a week.

You can watch the video which the ONS released with the data here (warning: it is particularly dry).

This is the last of three posts on today's 2011 Census data release. Our analyses of the latest figures on the UK's foreign-born population and religion can also be found on the Datablog site.

Download the data

• DATA: download the full spreadsheet

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Health
• Unemployment and employment statistics
• Unemployment
• Census

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

Muslims are the most ethnically diverse, Christians the oldest and Hindus are the most likely not to be born in the UK. Here is what the latest 2011 census data tells us
• Get the data
• More data journalism and data visualisations from the Guardian

Christianity has had a boost from people born overseas, nearly half of Muslims in England and Wales are under 25 and Hindus are the least likely of all the religious groups to be born in the UK according to the latest 2011 Census data release by the Office for National Statistics (ONS).

Christianity, which previous 2011 census data tells us is still the largest religious group in England and Wales with 33.2m people, has the oldest age profile of all the main religious groups.

One in five Christians is aged 65 or over. To put this into perspective, the percentage of Christians over the age of 65 is higher than the percentage of the population aged over 65 in 2011 - 22% compared with 16%.

In comparison, 88% of Muslims are under 50 and nearly half of Muslims are under 25. Although this isn't new, Muslims also had the youngest age profile in 2001, the number aged under 25 has increased by 505,000 in the past decade.

The largest decreases amongst those identifying themselves as Christians have been in the 30-39 age group and 5-14 year olds. The ONS explain that these decreases correspond with declines in these age groups in the overall population.

We know from previous data released by the ONS that a quarter of the population of England and Wales do not have a religion but for the first time we have more details on age and background. Four in ten people with no religion were aged under 25 and four in five are under 50, with the biggest increases seen amongst the 20-24 age group and those aged 40-44.

One of the key changes that the data released today highlights is the large increase in the number of Christians born outside the UK. Since 2001 the number of Christians born in the UK has decreased by 5.3m but the number of Christians born overseas has increased by 1.2m. Of those Christians born outside the UK, 887,000 are from EU accession countries (including Poland).

Another notable rise has been in the number of Muslims born in the UK - a rise of over half a million from 718,000 to 1.2m in 2011. The data also shows that Hindus are the least likely of all the religious groups to be born in the UK followed by Buddhists, but as the ONS note, this is a pattern seen previously.

Muslims are the most ethnically diverse religious group in England and Wales, followed by Buddhists according to the census figures. Over nine in ten Christians are white, this accounts for 30.8m people. People with no religion however, are the least ethnically diverse with 93% coming from a white background.

Click on the spreadsheet to get the 2011 census data.

Download the data

• DATA: download the full spreadsheet

More data

More data journalism and data visualisations from the Guardian

• Follow us on Twitter
• Like us on Facebook

• Religion
• Census
• Christianity
• Buddhism
• Sikhism
• Hinduism
• Atheism
• Office for National Statistics

Ami Sedghi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

At least 46% of foreign-born residents in England and Wales are British citizens, according to the latest set of 2011 Census data
Get the data
More data journalism and data visualisations from the Guardian
More from today's census data: religions
More from today's census data: unpaid carers

Just half of the foreign born population of England and Wales hold a non-UK passport and the vast majority of the non -white British population consider themselves British, according to new figures from the 2011 Census.

45.6% of usual residents born outside the UK hold a British passport, or 3.4m of the 7.5m foreign-born population.

When certain sections of the UK media debate immigration, there has been a tendency to equate "foreign born" with "not British" – but the new, more detailed, census figure shows this is seriously misleading: not only are at least 46% of foreign born people on these shores British, many of the rest consider themselves as such.

At country level, six of the top 10 foreign countries of birth have UK passport rates of over 50%, with Jamaica (72.8%) leading. Only one - Poland, with 4.9% - has a rate below one in five.

This matches figures for length of residency in the UK, with just one in 25 current Polish-born having arrived before 1981, compared to 59.8% of Jamaicans.

Anybody who holds a valid UK passport is a British citizen, but it is possible to become a citizen without a passport - most commonly when born to a parent who is a British citizen at the time.

In fact, the proportion of those from non -white British and mixed ethnicities who consider themselves British in some way is far higher than that indicated by type of passport.

It is actually only among those defining their ethnicity as Irish that less than half consider their national identity British, English, Welsh or any other combination of UK nationalities.

96.8% of mixed race White and Black Caribbean residents identify as British, with a further six minority ethnicities showing British national identity rates of over 80% (see chart below).

As you might expect, the general pattern suggests that the longer spent in the UK, the more likely somebody is to self-identify as British.

Alongside the Irish at the lower end of the scale are other white ethnicities (38.8%) - chiefly European - and Chinese (51.9%), other Asian (55%) and Arab (56.6%) groups.

The majority of the 'other white' group are relatively recent arrivals from the expanded EU, while the latter three groups have high representation in the student population.

85.9% of residents in England and Wales are white, compared to 81.2% of UK students, while 1.6% of students are Asian and 0.7% Chinese against population figures of 1.5% and 0.7% respectively.

Age profiles also vary considerably between ethnic groups. The median age across England and Wales as a whole is 39, with only three ethnic groups - white British, white Irish and those defining as Caribbean or Caribbean British - having a higher average.

Mixed ethnicity groups typically have the youngest populations, with white and black African (16), white and Asian (17) and non-British white and black Caribbean (18) all under 20.

National identity also varies with age - the 30-34 age group has the smallest proportion of UK-born members of all 5 year age groups in England and Wales, and also the lowest percentage who profess a British national identity of some form - 19.

This is the first of three posts on today's 2011 Census data release. Our analyses of the latest figures on unpaid carers and religious groups will follow.

A huge amount of census data was published today, so let us know what you've spotted – or what's been missed out – in the comments below, or via Twitter to me directly @jburnmurdoch or to the official @GuardianData account.

Download the data

• DATA: download the full spreadsheet

• SOURCE: ONS

NEW! Buy our book

• Facts are Sacred: the power of data (on Kindle)

More open data

Data journalism and data visualisations from the Guardian

World government data

• Search the world's government data with our gateway

Development and aid data

• Search the world's global development data with our gateway

Can you do something with this data?

• Flickr Please post your visualisations and mash-ups on our Flickr group
• Contact us at data@guardian.co.uk

• Get the A-Z of data
• More at the Datastore directory
• Follow us on Twitter
• Like us on Facebook

• Census
• Office for National Statistics
• Immigration and asylum

John Burn-Murdoch
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

The Department for Work and Pensions says 81% of non-resident parents pay the maintenance they should – but a charity says the real figure's much lower. What's going on?

With over one million cases on its books, the Child Support Agency - which calculates, collects and enforces child maintenance payments - is a critical part of the Department for Work and Pensions.

And because it affects so many households, child maintenance data is the subject of close scrutiny. Now Gingerbread, a campaign group for single parents, claims that the DWP are overestimating the proportion of non-resident parents who are up-to-date with their payments.

If they're right, tens of thousands of children of separated parents could be missing out on money that's owed to them, without this appearing anywhere in the official figures.

In Wednesday's statistical release, the DWP claimed that 81% of maintenance cases were being paid. The number has been accused of being 'misleading' because of the way it defines a positive maintenance outcome.

Being 'positive' about outcomes

The DWP define a parent as 'compliant' and a CSA arrangement as 'effective' if any proportion of any maintenance payment is made.

A case is classed as having a positive maintenance outcome if a payment has been received via the collections service in the quarter, or if a maintenance direct arrangement is in place.

There's more on "direct" maintenance – in short, payments which aren't administered by the CSA – below, but for now what's important is the basic wording of "a payment".

What that means in practice is that a parent need only pay a fraction of just one of the 12 weekly or three monthly payments to be included as a positive outcome in the quarterly statistics - causing groups like Gingerbread to claim that this masks the full extent of non-payment.

In an extreme (hypothetical) case, it seems, a parent paying a single penny of a single installment of child maintenance would count as compliant under the DWP's measure.

MP Cathy Jamieson found this definition confusing and so asked for further detail in a House of Commons debate last month. The reply she received, reproduced below, suggests that assuming full payment may well be misleading.

What's more, Gingerbread believe that even the 58% compliance figure in the table above might be misleading. This is because, as the DWP definition above shows, it includes all maintenance direct payments and assumes that these were paid in full.

So what exactly is maintenance direct and why would it be wrong to assume it's paid in full?

Maintenance direct

The Child Support Agency offers two types of service: one where they calculate liability and collect payments and one where they just calculate liability and leave payment collection to be arranged between parents. The second of these is known as Maintenance Direct, and, given that it is probably less costly, the DWP "want them [parents] to actively consider Maintenance Direct in the first instance".

According to their most recent release, 188,900 of the cases which the CSA deals with are Maintenance Direct - which represents of 21% of all cases where a parent was considered liable for child maintenance payments.

Gingerbread chief executive Fiona Weir said:

"The DWP itself predicts that as more families set up direct payments, once the new child maintenance service starts charging to collect, only one in four (28%) of these arrangements will be paid in full and on time. The department cannot therefore claim to believe that all existing direct pay arrangements are compliant, and it seems extraordinary that it would continue to over-claim in this way.

We contacted the DWP for comment but at the time of writing, have yet to receive a reply.

If you have a comment about this piece, you can post it below or tweet to @GuardianData.

Update: Since publishing this article, the DWP have got back to us with the following statement.

"We stand by the accuracy of our figures. What we are consulting on is providing more information, not less. Let's not lose sight of the fact that, even compared with six years ago, hundreds of thousands more children are benefiting from payments being made in the CSA."

• Divorce
• Childcare

Mona Chalabi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds

New figures published by Harriet Harman show 82% of presenters on TV over the age of 50 are men. Which broadcasters are best and worst?
• Get the data
• More data journalism and data visualisations from the Guardian

A shocking 82% of broadcast presenters over the age of 50 are men, new figures have revealed. The research released today by deputy leader of the Labour party, Harriet Harman shows even though the majority of over 50s in the UK are women, the overwhelming majority of TV presenters over that age are men.

Harman, who also holds the posts of shadow deputy prime minister and shadow culture secretary, wrote to the six major UK broadcasters; BBC, ITN, ITV, Channel 4, Channel 5 and Sky News, to see how many women they employ on screen, behind the camera and how many of those are over the age of 50.

"The figures provided by broadcasters show clearly that once female presenters hit 50, their days are numbered," said Harman who is due to hold a roundtable with broadcasters in the House of Commons today. Although Harman does believe that the production of these statistics from the broadcasters shows promise and is "encouraging", she also thinks there is "a combination of ageism and sexism that hits women on TV that doesn't apply to men."

The figures shine a light on an issue that broadcasters have faced increasing criticism for. Back in 2011, axed Countryfile presenter Miriam O'Reilly took the BBC to an employment tribunal for age discrimination and won her case.

37% of the total workforce, both on and off screen are women over the age of 50, according to the aggregate data. And whilst TV presenters under 50 are generally representative of the gender balance in the UK population (48% of presenters under 50 are women compared to 49.7% of women under 50 in the general population), when it comes to female TV presenters over 50 this drops to just 18%.

So how do the figures break down by broadcaster? Only 9% of presenters over the age of 50 at the Sky News are women, not exactly fitting with their viewing demographics; average age of viewers is 46 and 38% of viewers are female.

However, this is still a far better result than either ITN or Channel 5 can boast with zero. ITV recorded the highest percentage at 55% but unlike the other broadcasters studied, the figures they responded with cover the number of presenters over the age of 55. Today's release also does note that as ITV only provided percentages and no raw numbers they are not included in the aggregate data.

The BBC, though, have complicated matters also by including on-air radio presenters in their response to Harman. If they respond again with more accurate figures, we'll update the post, but are using what we've got for now.

If we're to turn our attention to the total workforce, both on and off screen, then the percentages for women over 50 are much higher. 46% of the total workforce at Channel 4 are women over 50, 37% at the BBC and 24% at ITN. 34% of ITV's total workforce are women over the age of 55. No data was received from Channel 5 or Sky News.

The table below shows a summary of results. Please note that as Channel 4 have no in-house production base, they do not produce, develop or appear in their programmes and therefore were unable to provide on-screen statistics to the commission. As explained above, ITV do not appear in the aggregate data as they only provided percentages and not raw numbers. The full data and breakdown by broadcaster and question asked by Harman is available in the downloadable spreadsheet.

Data summary

Download the data

• DATA: download the full spreadsheet

More data

More data journalism and data visualisations from the Guardian

• Follow us on Twitter
• Like us on Facebook

• Television
• Women
• BBC
• ITN
• ITV channel
• Channel 4
• Channel 5
• Sky News
• Equality
• Harriet Harman
• Labour

Ami Sedghi
guardian.co.uk © 2013 Guardian News and Media Limited or its affiliated companies. All rights reserved. | Use of this content is subject to our Terms & Conditions | More Feeds