-88.89% is the change from 180 to 20
Calculation steps:
[( 20 - 180 ) ÷ 180] x 100 = -88.89%
Formula
Percentage change = [(20 - 180) / 180] x 100
Subtract the new number by the original number
20 - 180 = -160
-160 ÷ 180 = -0.8888888888888888
-0.8888888888888888 x 100 = -88.89%