590% is the change from 90 to 621
Calculation steps:
[( 621 - 90 ) ÷ 90] x 100 = 590%
Formula
Percentage change = [(621 - 90) / 90] x 100
Subtract the new number by the original number
621 - 90 = 531
531 ÷ 90 = 5.9
5.9 x 100 = 590%
Example