-89.2% is the change from 287 to 31
Calculation steps:
[( 31 - 287 ) ÷ 287] x 100 = -89.2%
Formula
Percentage change = [(31 - 287) / 287] x 100
Subtract the new number by the original number
31 - 287 = -256
-256 ÷ 287 = -0.89198606271777
-0.89198606271777 x 100 = -89.2%