However, after reaching its peak in the early 1990s, the Gini rises more slowly, reduces slightly in the wake of the 1992 recession and then fluctuates during the Blair years. But then, here’s the really surprising thing, as we go past the 2008 banking crisis, income inequality actually starts to reduce, taking us back to levels last seen in the late 1980s. This happened because the great recession resulted in rich people getting slightly less rich while poorer people are taken out of income tax thanks to one of the Coalition government’s more enlightened pieces of fiscal reform.

And that’s the problem for the left, inequality – by established measures – is actually falling, not by much, but still going in what most progressives would say is the right direction. There’s no guarantee this will continue, there’s some evidence that the top strata of the rich are beginning to pull away from the rest of us while at the same time average incomes will stagnate until at least 2020. In fact, many of the changes to benefits – which affect millions of working families – haven’t been felt fully yet. But for the moment, the Left has big problem. As the centre right argues, why does inequality matter as long as the poor’s incomes continue to grow while those at the top of the pile pay their share in tax? Everyone gets richer, everyone benefits.

And if the gap is decreasing anyway under a Conservative Government, where does the Left’s traditional redistribution argument go? Do you argue that you want to reduce it further and faster? That soon leads you into politically tricky territory; recently Jeremy Corbyn suggested capping the incomes of some unspecified high earners, and it  didn’t play well. Plus the baby boomers who remember the golden age of income equality will be in their mid- to late-seventies by 2020 and that means a good chunk of the electorate won’t remember a time when incomes were more equal.