There is little evidence that large numbers of international students overstay their visas in the United Kingdom, according to a report from the Office for National Statistics (ONS). Roughly 97% of the 181,000 international students whose visas expired in 2016–17 left the United Kingdom after their studies concluded, says the report, debunking previous estimates that as many as 50,000 overseas students stay on illegally. The report cites data that are based on exit checks introduced in 2016. It says these figures more accurately reflect student behaviour than do earlier numbers calculated on the basis of the 'International Passenger Survey', a set of questions asked of people leaving the United Kingdom at ports or airports to determine their future plans. In its report, the ONS said it will continue to study immigration and emigration patterns, and identified a need for a greater emphasis on the complexities of life for international students. The office is expected to release plans for improving its statistics this month. The latest data have led to renewed calls for students to be taken out of UK net-migration targets.