-70.42% is the change from 71 to 21
Calculation steps:
[( 21 - 71 ) ÷ 71] x 100 = -70.42%
Formula
Percentage change = [(21 - 71) / 71] x 100
Subtract the new number by the original number
21 - 71 = -50
-50 ÷ 71 = -0.704225352112676
-0.704225352112676 x 100 = -70.42%