Hopi expects that Ed Miliband's speech on wages next week could say that "not enough of our national income has been going to the many." A glance at the national accounts data, however, suggests this claim is problematic.

My chart shows wage and profit shares since quarterly data began in 1955.It shows that the wage share - the proportion of national income going to the many - is now around its post-2000 average. Polly's right to say that the wage share fell "long before the crash". But it did so between 1975 and 1997. It's the profit share that is unusually low by recent standards, not the wage share.

This shouldn't be surprising. For one thing, the profit share is partially cyclical; it tends to fall in recessions and slowdowns. And for another, productivity has fallen, which suggests that one way in which capitalists exploit workers - getting them to work more intensively - has weakened in this recession.

Duncan is right to say we have a wage crisis rather than a cost of living crisis. But wages are low because the economy is weak, rather than because capitalists have been grabbing a bigger share of the cake recently.

All this said, you could still argue that the wage share is too low and the profit share too high, in two ways:

1. Any amount going to profits is unjust. This is because profits are a sign that workers are being exploited (pdf), and capitalists do nothing to justify such a return. There's good evidence, for example, that firms with external shareholders have lower capital spending, worse corporate culture and inadequate control over management.

2. Even though the profit share is quite low by recent standards, a shift in incomes from profits to wages might be a good thing, if the propensity to spend out of wages is higher than that to spend out of profits.

Claim 1 is, I fear, too radical for Miliband junior. And claim 2 is probable rather than certain.

So where does this leave us? Simple. The most obvious solution is the wage crisis isn't to shift the share of incomes - I share Hopi's scepticism about micro-interventions - but simply to increase the demand for labour through macroeconomic policy. Sadly, though, with monetary policy of dubious efficacy, looser fiscal policy ruled out - because it just is, all right? - and jobs guarantees used to harass the jobless rather than to provide an employer of last resort, such policies probably won't be equal to the scale of the task.