4160% is the change from 15 to 639
Calculation steps:
[( 639 - 15 ) ÷ 15] x 100 = 4160%
Formula
Percentage change = [(639 - 15) / 15] x 100
Subtract the new number by the original number
639 - 15 = 624
624 ÷ 15 = 41.6
41.6 x 100 = 4160%
Example