2180% is the change from 15 to 342
Calculation steps:
[( 342 - 15 ) ÷ 15] x 100 = 2180%
Formula
Percentage change = [(342 - 15) / 15] x 100
Subtract the new number by the original number
342 - 15 = 327
327 ÷ 15 = 21.8
21.8 x 100 = 2180%
Example