1300% is the change from 15 to 210
Calculation steps:
[( 210 - 15 ) ÷ 15] x 100 = 1300%
Formula
Percentage change = [(210 - 15) / 15] x 100
Subtract the new number by the original number
210 - 15 = 195
195 ÷ 15 = 13
13 x 100 = 1300%
Example