-6.38% is the change from 235 to 220
Calculation steps:
[( 220 - 235 ) ÷ 235] x 100 = -6.38%
Formula
Percentage change = [(220 - 235) / 235] x 100
Subtract the new number by the original number
220 - 235 = -15
-15 ÷ 235 = -0.06382978723404255
-0.06382978723404255 x 100 = -6.38%