-22.56% is the change from 820 to 635
Calculation steps:
[( 635 - 820 ) ÷ 820] x 100 = -22.56%
Formula
Percentage change = [(635 - 820) / 820] x 100
Subtract the new number by the original number
635 - 820 = -185
-185 ÷ 820 = -0.22560975609756098
-0.22560975609756098 x 100 = -22.56%