-21.64% is the change from 818 to 641
Calculation steps:
[( 641 - 818 ) ÷ 818] x 100 = -21.64%
Formula
Percentage change = [(641 - 818) / 818] x 100
Subtract the new number by the original number
641 - 818 = -177
-177 ÷ 818 = -0.21638141809290953
-0.21638141809290953 x 100 = -21.64%