The median income for a man in 1940 was $956. In 2010, the median income was $33,276. Women in 1940 earned 62 cents for every dollar a man earned. In 2010, women earned 74 cents for every dollar a man earned. In 2019 the income numbers probably has grown by another 20% just because of inflation.

So basically education cost grows only slightly faster than median income. Given the biggest portion of the cost is human capital, this makes economical sense.

reference: https://www.npr.org/2012/04/02/149575704/the-1940-census-72-...