2540% is the change from 15 to 396
Calculation steps:
[( 396 - 15 ) ÷ 15] x 100 = 2540%
Formula
Percentage change = [(396 - 15) / 15] x 100
Subtract the new number by the original number
396 - 15 = 381
381 ÷ 15 = 25.4
25.4 x 100 = 2540%
Example