-31.82% is the change from 220 to 150
Calculation steps:
[( 150 - 220 ) ÷ 220] x 100 = -31.82%
Formula
Percentage change = [(150 - 220) / 220] x 100
Subtract the new number by the original number
150 - 220 = -70
-70 ÷ 220 = -0.3181818181818182
-0.3181818181818182 x 100 = -31.82%