When tax rates are too high, a decrease in tax rates will cause a(n) in the tax revenue.

decrease.

Explanation:

The laffer curve is a curve that is used to describe the relationship between the tax rate and tax revenue. if government-induced high tax rates then it directly affects the tax revenue due to the negative impact on investment activities. while on the other side if the government cut the tax rate then it will encourage the economic stability and enhance the tax revenue

is there a year set? the question is incomplete

for your question the answer would have to be france