-82.78% is the change from 180 to 31
Calculation steps:
[( 31 - 180 ) ÷ 180] x 100 = -82.78%
Formula
Percentage change = [(31 - 180) / 180] x 100
Subtract the new number by the original number
31 - 180 = -149
-149 ÷ 180 = -0.8277777777777777
-0.8277777777777777 x 100 = -82.78%