-86.36% is the change from 220 to 30
Calculation steps:
[( 30 - 220 ) ÷ 220] x 100 = -86.36%
Formula
Percentage change = [(30 - 220) / 220] x 100
Subtract the new number by the original number
30 - 220 = -190
-190 ÷ 220 = -0.8636363636363636
-0.8636363636363636 x 100 = -86.36%