-8.33% is the change from 240 to 220
Calculation steps:
[( 220 - 240 ) ÷ 240] x 100 = -8.33%
Formula
Percentage change = [(220 - 240) / 240] x 100
Subtract the new number by the original number
220 - 240 = -20
-20 ÷ 240 = -0.08333333333333333
-0.08333333333333333 x 100 = -8.33%