You are right, Federal receipts have been hovering between ~15-17% of GDP since WWII, regardless of whether the top tax rate was 90% or 28%. There is more varia

You are right, Federal receipts have been hovering between ~15-17% of GDP since WWII, regardless of whether the top tax rate was 90% or 28%. There is more variation due to changes in growth than changes in rates. https://fred.stlouisfed.org/series/FYFRGDA188S https://fred.stlouisfed.org/series/FYFRGDA188S