The UK’s Office for National Statistics (ONS) has recently produced estimates of the number of British citizens living in the European Union (EU). The numbers, apparently, have declined from 1.22m prior to 2017, to “around 900,000” (Jan 2017), and more latterly to 784,900 (April 2018).
Meanwhile, our research has revealed that most informed commentators (academics, local government officials, consular offices, and others who work with the British abroad) understand numbers to have changed little since 2008, and that the correct, conservative, estimate is closer to 1.8m.
So, what is going on? Where do these estimates come from? And why does the drop matter?
According to the ONS, its estimates, which are reproduced widely by campaign and interest groups, academics, politicians and journalists, are published “in response to an increased user need for data about the people who may be most likely to be affected by the UK’s decision to leave the EU”. The ONS argues that the heretofore trusted United Nations data (source of the 1.22m estimate) are unreliable “high-level estimates” based on extrapolating out from census data. The ONS said in 2017 that it prefers to use “more detailed census data”, leading to the first, inadequately explained, reduction to 900,000.