well, $100 in 1990 is equivalent in purchasing power to about $240.30 today (source) so 21 usd/h should be about 50 usd/h today and the 62.5 usd/h calculated by @[email protected] should be 150 usd/h
Value of 1990 dollars today | Inflation Calculator
The 2.61% inflation rate means $100 in 1990 is equivalent to $240.30 today. This inflation calculator uses the official US consumer price index published by the Department of Labor.