As a wealth of data continues to pour out from the 2011 census, we need to remind ourselves how valuable it is. Government suggestions that this census might be the last one are nonsensical and should be resisted.
Not long after the last census took place, stories began to emerge that the government believed that the £500m cost simply wasn’t worth it. It was even suggested that the 2021 census could be replaced by scrutiny of supermarket store cards. Government was later reported to be looking for ‘more effective, less bureaucratic’ ways of collecting data.
These moves were announced before the detailed results even began to emerge. Will the obvious usefulness of the data now being released help to change their minds?
Local government had reason to be sceptical about the census in the wake of the 2001 results. In that year, it under-counted the population and under-represented immigration. As the census coincided with a surge of new migration, councils quickly got frustrated that their pleas for extra help to provide services to growing populations fell on deaf ears: old data were constantly cited by government as grounds for maintaining the status quo.
The Office for National Statistics (ONS) seems to have learnt its lessons. The 2011 data came out quickly, the coverage of the latest census is extraordinarily high and the results flesh out in great detail the trends that we’ve known about more generally from other surveys.
Most important of all, whereas sources like the International Passenger Survey log inward and outward movements of people on a regular basis for the UK as a whole, the census tells us exactly where they come from and go to, which is the information that local service providers need.
Here’s an example of how the results can be used. HACT, the charity and thinktank, has developed a free resource for housing providers called Population Insight. It takes highly detailed census data on diverse communities and immigration and provides it in a form that housing providers can tailor to show the detail for local areas or even particular streets.
For example, one of the headline changes across Britain has been the growth in the foreign-born population from 7%in 2001 to 13% in 2011. But some places are hardly touched by immigration, while others have been transformed.
Metropolitan Housing Group used Population Insight to assess change in areas where it works, and found that in one patch of Barking and Dagenham with under 2,000 residents the ‘white British’ population had fallen from 88% to 48%. Several minority groups had grown significantly, the biggest increase being among Black Africans (up 313 people from 2001).
This is the kind of fine-grained information only the census can provide, and service providers can then dig further (for example, Population Insight will tell them how many households don’t speak English).
Here’s another example. Important government forecasts, such as projections of the future growth in household numbers, are based on inter-census surveys and other records. The ten-yearly census enables statisticians to rebase their figures. The current projections for England use estimates of numbers of households in 2008; the next set early this year will be able to take account of the census’s finding that household numbers are actually lower than was thought.
Now, if ministers aren’t keen on the census, they are nevertheless keen on using these projections, as the gap between household growth (currently projected at 232,000 per year) and new housebuilding (barely topping 100,000) is regularly cited. Don’t they therefore have a strong interest in the accuracy of these figures?
It beggars belief that supposedly cheaper measures like scrutinising store cards could provide similar high-quality data to those from the census. We risk entering an epoch when we no longer know about our own population with any accuracy, since people who don’t have store cards, bank accounts or other accessible information, or who have recently arrived from abroad, could be missed out.
In any case, information will be reduced to that which is commercially viable for private operators to record and provide.
Danny Dorling, a geographer who has never been afraid to use census and other data to criticise governments, has sketched out how the dropping of future censuses might affect local authorities.
The way that Dorling and other researchers make use of the census often uncovers inconvenient truths. But however uncomfortable, we ought to insist that we still need to know about them.
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