How have the earnings of the us workers changed over the last 30 years?

In the years just before the 2007-08 financial collapse, average hourly earnings often increased by around 4% year-over-year. And during the high-inflation years of the 1970s and early 1980s, average wages commonly jumped 7%, 8% or even 9% year-over-year.

- Sincerely, Ouma

your answer would be just capitalism.