-88.89% is the change from 270 to 30
Calculation steps:
[( 30 - 270 ) ÷ 270] x 100 = -88.89%
Formula
Percentage change = [(30 - 270) / 270] x 100
Subtract the new number by the original number
30 - 270 = -240
-240 ÷ 270 = -0.8888888888888888
-0.8888888888888888 x 100 = -88.89%