-81.65% is the change from 109 to 20
Calculation steps:
[( 20 - 109 ) ÷ 109] x 100 = -81.65%
Formula
Percentage change = [(20 - 109) / 109] x 100
Subtract the new number by the original number
20 - 109 = -89
-89 ÷ 109 = -0.8165137614678899
-0.8165137614678899 x 100 = -81.65%