-96.3% is the change from 270 to 10
Calculation steps:
[( 10 - 270 ) ÷ 270] x 100 = -96.3%
Formula
Percentage change = [(10 - 270) / 270] x 100
Subtract the new number by the original number
10 - 270 = -260
-260 ÷ 270 = -0.9629629629629629
-0.9629629629629629 x 100 = -96.3%