-84.56% is the change from 136 to 21
Calculation steps:
[( 21 - 136 ) ÷ 136] x 100 = -84.56%
Formula
Percentage change = [(21 - 136) / 136] x 100
Subtract the new number by the original number
21 - 136 = -115
-115 ÷ 136 = -0.8455882352941176
-0.8455882352941176 x 100 = -84.56%