We can see that membership rose to a first peak at the end of the First World War, both by headcount and as a share of the workforce.

The figures then went into steep decline until the lowest ebb of the Great Depression in 1933, before decisive gains during both the pre and post-war period.

These gains accelerated from 1968 (following a successful 100th anniversary campaign?!) until they peaked – when else? – in 1979.

From that point, however, trade union membership has been in retreat (though the latest figures show a slight increase in 2018).

But while membership numbers are clearly at a low ebb right now, the history gives us a sense of the possibilities that could lie ahead.

Just forty years ago, over half of the workforce were members of a trade union. Today it is barely 20%.

So as we reflect on 150 years of the TUC, it’s clear we need to find a way to inspire new generations to join and sustain the movement for another century and a half.

One of the ways to do so is by reminding people that stronger unions mean a stronger economy – and that means better paid jobs for everyone.

Stronger unions, better wages

Labour market comparisons over the last century and a half show the power of strong unions.

This is demonstrated in the next chart: