During the “relative halcyon days” of the initial post-war decades both personal savings and spending were increasing each year. Then something happened, beginning in the latter 70s. Both spending and savings started dropping, though the savings rate has picked up a bit over the last ten years—but still far below the level in the 60s and early 70s.
In the above chart we see that personal income per capita has steadily risen since 1960, though it actually fell slightly during the Great Recession. So, why are both spending and savings down if income is up? Well, that red curve above shows the Gini index, a measurement of inequality. More and more of the economy’s output finds its way into the bank accounts of the few. Indeed, the rich have accumulated so much wealth that they really have no place to spend it all. The Rest of Us, on the other hand, spend nearly all that we make, and we’re not making as much as we used to.
That said, the spending by the rich on the kinds of things we need—especially housing—inflates prices beyond the reach of the ordinary. The wealthy are driving out the Rest of Us and the businesses we depend on. See this piece by Tim Wu in The New Yorker.