The study looked at a total of more than 20,000 British men and women in four birth cohorts from 1946, 1958, 1970 and 1980-84. The researchers worked with the 7-class version of the official National Statistics Socio-Economic Classification (NS-SEC), in which individuals are given social classes on the basis of their employment status and occupation. They compared the class of each individual when in their late-20s or 30s with the class of their fathers, and found that around three-quarters of men and women alike ended up in a different class to the one they were born into, and that this proportion was more or less constant across the four cohorts.

But, as lead author Associate Professor Erzsébet Bukodi, from the Department of Social Policy and Intervention at the University of Oxford, stresses: ‘There is a clear change in the direction of mobility. Over the past four decades, the experience of upward mobility has become less common, and going down the social ladder has become more common.’

The study explains that this is due to the changing class structure. From the 1950s to the1980s there was a major expansion of professional and managerial employment – ever more ‘room at the top’. But this expansion has now slowed down, and the children of those who benefited from it through upward mobility now have less favourable prospects than their parents had when they were young.

Bukodi explains: ‘It is not that there has been an increase in the risk of downward mobility but rather an increase in the numbers “at risk”, or the proportion of children starting off in professional and managerial families.’

The study also finds that inequalities in the chances of individuals of different class origins ending up in different class destinations have not increased – though neither have they been reduced. Moreover, for men and women alike the inequalities are significantly greater than previously thought – and much greater than if, for example, only income mobility were considered. For example, the chances of a child with a higher professional or managerial father ending up in a similar position rather than in a wage-earning working-class position are up to 20 times greater than these same chances for a child with a working-class father.

Co-author and Oxford sociologist, Dr John Goldthorpe, concludes: ‘Politicians are saying that a new generation of young people don’t have the same opportunities for social advancement as their parents, and these results seem to bear that out. The trend shows that while social mobility has not stalled, more mobility is going in a downward direction than in the past. The emerging situation is one for which there is little historical precedent and that carries potentially far-reaching political and wider social implications.’

The researchers used data from the National Survey of Health and Development (1946), the National Child Development Study (1958), the British Cohort Study (1970) and the UK Household Longitudinal Study (1980-84).