Yes, but it's not like the stock market. In Japan the stock market peaked in 1989. If you invested all your money at that time you would have broken even after dividends now, maybe.
A peak in compensation doesn't work like that, since you couldn't "invest" in 1973 and "lose money".
It's more like from the 1964 to 1994 you have a flat graph with a peak, but from 1994 to the present it's been getting better for the last 30 years.
Productivity is another thing, for one, medical insurance costs employers a lot more and it's not included in wages, but included in total compensation