If you are reading this, it is likely that you are: 1) A young graduate living in a city, 2) You voted for Labour in 2017 and, 3) Most of your friends, especially where you live, voted for Labour too.

Some of you will be economic migrants who moved to a city as part of the UK’s Great Graduate Migration. Each year, tens of thousands of graduates like you move to cities (and London, in particular) seeking brighter lights and better jobs. This Great Graduate Migration helps to fuel economic growth within cities and, as a result, these cities are growing much faster than the towns and villages that surround them. But while young graduates (like you) are moving to growing cities where the best jobs with the highest pay are, older non-graduates are moving out or staying away.

This is having an effect on how people and places vote. The fact that age is a new political fault line in British politics has been well covered elsewhere. What has been less commented upon, however, is that there is another political fault line that encircles cities, separating them from the surrounding towns and villages. It is not just the young and the old that are voting in increasingly different ways; cities and non-cities are also voting in increasingly different ways as well. Age-based political polarisation has been mirrored by political segregation.

In order to show this, I have constructed a simple Political Segregation measure (Figure 1 below), using constituency voting data for England and Wales. Values that are further from zero indicate a greater level of political segregation.

Political Segregation is calculated here as the percentage point difference between the average Labour share of the vote in each city-type constituency and the average Labour share of the vote in all English and Welsh constituencies. For example, in 2010, an average of 39.5% of those in large city constituencies voted for Labour. For all English and Welsh constituencies, an average of 30% voted for Labour in 2010. Political Segregation is the difference between the two: 9.5 percentage points.

Looking at Figure 1, it is clear that cities have become significantly more pro- Labour and non-cities have become significantly less pro-Labour since 2010 i.e. political segregation has increased. Looking at Figure 2 below, we can see that this has been mirrored by an increase in age-based political polarisation. Since 2010, young people have become significantly more likely to vote for Labour whilst older people have become significantly less likely to vote for Labour.

Source: Ipsos Mori “How Britain Voted”

The political fault lines of age and place have grown wider over the past decade as young graduates became more pro-Labour and moved to the cities, which also became more pro-Labour in turn. At least one of these trends is likely to continue. Young graduates will probably keep moving to the cities where the largest pool of potential employers are. If young people also remain as (or become more) pro-Labour, then these cities may also become even more pro-Labour in the future. In other words, while the political fault lines of age and place may appear wide today, they could grow even wider in the years to come.