-89.47% is the change from 285 to 30
Calculation steps:
[( 30 - 285 ) ÷ 285] x 100 = -89.47%
Formula
Percentage change = [(30 - 285) / 285] x 100
Subtract the new number by the original number
30 - 285 = -255
-255 ÷ 285 = -0.8947368421052632
-0.8947368421052632 x 100 = -89.47%