My first job after college, as a trainee with JC Penney in Sacramento, paid $5400 in 1965. Within three years I had two kids to support, but my income was up to about $7500. I worked 48-54 hours a week and did grad studies at night at Sacramento State. We had a 1956 Buick and a 1960 VW. In 1971, I started writing about economics on the side.
My labor income peaked around 1999 (by working three jobs) and is now about a fourth of what it was then. I know something about the lower and upper fifths of the income distribution and also about mobility between them.