-15.41% is the change from 331 to 280
Calculation steps:
[( 280 - 331 ) ÷ 331] x 100 = -15.41%
Formula
Percentage change = [(280 - 331) / 331] x 100
Subtract the new number by the original number
280 - 331 = -51
-51 ÷ 331 = -0.1540785498489426
-0.1540785498489426 x 100 = -15.41%