1260% is the change from 15 to 204
Calculation steps:
[( 204 - 15 ) ÷ 15] x 100 = 1260%
Formula
Percentage change = [(204 - 15) / 15] x 100
Subtract the new number by the original number
204 - 15 = 189
189 ÷ 15 = 12.6
12.6 x 100 = 1260%
Example