[giantg2]

The middle class has also shrunk, right?

Those advances are adjustments in quality of living driven by efficiencies in manufacturing, etc. This would be more on the resource scarcity side and less on the rich/income side. I would exclude food as an indicator since that is heavily subsidized. Healthcare has also increased substantially as a percentage of income.

[PeterisP]

The global middle class has grown but the USA middle class has shrunk due to some rebalancing/equalization with other countries.

[giantg2]

Yeah, that rebalancing and equalizing was what I was mostly the effect I was wondering about or getting at.