18 Apr 2021 A report from the Migration Observatory at the University of Oxford has estimated that the Office for National Statistics (ONS) undercounted net EU migration to the United Kingdom by an average of 93,000 per year between 2012 and 2020. The study estimated that, in total, net migration to Britain was 15 per cent higher than previous estimates from the ONS, with many more people entering the country than initially believed. The discrepancy between the former figures and the reality came as a result of the structural problems inherent in the previous immigration counting system — the International Passenger Survey — which was in effect until recently.