Study found no significant increase in youth turnout but critics say definition of young people is too narrow

The idea that Labour’s better-than-expected performance in last year’s UK general election was down to a “youthquake” surge in younger voters is a myth not backed up by detailed turnout figures, a study has concluded.

A post-election survey of voter behaviour by the British Election Study (BES) found there is no evidence of any significant increase in voting among young people, and that among the youngest voters it might have even fallen. Instead, the study finds, the only notable rise in the numbers of voters going to the polls was for those aged 30-40.

A report by the study team says the idea of the so-called youthquake – a term so resonant it was chosen by Oxford Dictionaries as its word of 2017 – was based partly on assumption, and partly on flawed post-election polls.

Critics argued that the study’s definition of young people was too narrow to measure significant changes in turnout against the previous election.

Aaron Bastani (@AaronBastani) What this gets completely wrong is that 'young people' doesn't mean under-24s - in our broken system it means under-45s https://t.co/ug6RlAjHty

David Ottewell (@davidottewell) Okay so I understand why people are saying "there was no youthquake!" but that increase in turnout among 25-40 year olds is _really_ significant. Not "youths" maybe, but young adults. That _would_ be the story if just saw this graph in isolation, and rightly so. pic.twitter.com/AjEijIo7hg

But the report argues that the idea of Jeremy Corbyn being swept along in a tide of youthful support was propagated by sights such as the Labour leader’s name being sung by crowds at the Glastonbury festival, and the party’s strong social media strategy.

The idea was then cemented by data showing turnout rising strongly in constituencies with lots of young people, and post-election polling claiming that turnout among voters aged 18-24 had risen by anything from 12 to 16 percentage points.

However, the BES team note, measuring turnout in polls, especially those conducted by phone or internet, is notoriously difficult. That is partly because nonvoters are much less likely to take part in such surveys, and because some then say they voted when they did not.

The BES data, a system used since 1964, is based on face-to-face interviews carried out by knocking on the doors of thousands of addresses across the country selected at random, with answers verified by checking the electoral register.

The BES system contains some margin of error, the report says, meaning a small rise – or fall – in the youth vote cannot be ruled out. However, it adds: “We can be confident, though, that there was no dramatic surge in youth turnout of the sort suggested by some other surveys. In short, there was no ‘youthquake’.”

This should not come as a surprise, the report says, given voting is well known to be “sticky”, meaning voters and nonvoters tend to keep their habits at successive elections, and that older people remain more likely to vote.

The study does find that Labour’s share of the youth vote increased last year compared with the 2015 general election, but that this did not mean the youth turnout rose as well. It notes also that the party’s popularity increased among all age groups apart from those over 70.

It also found a big increase between the elections in older voters tending to back the Conservatives, seemingly as many moved from Ukip after the Brexit referendum.