-33.23% is the change from 331 to 221
Calculation steps:
[( 221 - 331 ) ÷ 331] x 100 = -33.23%
Formula
Percentage change = [(221 - 331) / 331] x 100
Subtract the new number by the original number
221 - 331 = -110
-110 ÷ 331 = -0.3323262839879154
-0.3323262839879154 x 100 = -33.23%