[영문]Barro?style models of endogenous growth imply that economic growth will initially rise with an increase in taxes directed toward economically qqqquot;productiveqqqquot; expenditures (e.g., education,highways, public safety), but will subsequently decline?consistent with a qqqquot;growth hillqqqquot;?as the rising tax share depresses the net return to private capital. Previous tests focus on whether thelinear incremental effect of taxes is positive, negative, or zero, with substantial evidence for all three conclusions. This study incorporates potentially non?monotonic effects for fiscal policy. Based onestimates for U.S. states, the incremental effect of taxes directed toward publicly provided productive inputs is initially positive, but eventually turns negative, consistent with a growth hill.