…the incomes of rich and poor families have drawn further apart.
Let\’s take that as true (for households it definitely is in fact).
Seems an interesting question really. The answer is, at least in part (I would argue in large part but don\’t have the figures to prove it) assortative mating.
We match up, marry, have children, later than we used to. Nearly a full decade later in fact on average. We tend to meet our mates through our work these days (not an unlikely thing for those hitching up in their late 20s). This is rather different from the matching up when marriage ages were lower.
So, now, we tend to match up with those following a similar life path to our own, rather than simply with someone from the same geographical or extended familial networks. This leads to the rise of the two professionals marriage, something that was really rather rare in decades past.
Who are those households at the top of the household income distribution? The two professionals households.
One of the reasons (and as above, I would argue, one of the major ones) for the divergence in household incomes is simply a change in the mating habits of the population. Professionals tend to marry professionals, non-professionals non-, much more than used to be the case. So we end up with households with two professional incomes and households with none, where we might in the past have had two households with one professional income each.
As I keep trying to emphasise here we\’ve got to try and work out why certain things happen if we\’re ever to have any hope of correcting perceived problems: or, indeed, of deciding that that why means that the result is not a problem.
Now, if it is true that assortative mating is behind the rise in variance of household incomes, what in buggery could we possibly do about it? Insist that accountants marry proles?