2420% is the change from 15 to 378
Calculation steps:
[( 378 - 15 ) ÷ 15] x 100 = 2420%
Formula
Percentage change = [(378 - 15) / 15] x 100
Subtract the new number by the original number
378 - 15 = 363
363 ÷ 15 = 24.2
24.2 x 100 = 2420%
Example