-84.58% is the change from 590 to 91
Calculation steps:
[( 91 - 590 ) ÷ 590] x 100 = -84.58%
Formula
Percentage change = [(91 - 590) / 590] x 100
Subtract the new number by the original number
91 - 590 = -499
-499 ÷ 590 = -0.8457627118644068
-0.8457627118644068 x 100 = -84.58%