2900% is the change from 21 to 630
Calculation steps:
[( 630 - 21 ) ÷ 21] x 100 = 2900%
Formula
Percentage change = [(630 - 21) / 21] x 100
Subtract the new number by the original number
630 - 21 = 609
609 ÷ 21 = 29
29 x 100 = 2900%
Example