900% is the change from 15 to 150
Calculation steps:
[( 150 - 15 ) ÷ 15] x 100 = 900%
Formula
Percentage change = [(150 - 15) / 15] x 100
Subtract the new number by the original number
150 - 15 = 135
135 ÷ 15 = 9
9 x 100 = 900%
Example