20.37% is the change from 491 to 591
Calculation steps:
[( 591 - 491 ) ÷ 491] x 100 = 20.37%
Formula
Percentage change = [(591 - 491) / 491] x 100
Subtract the new number by the original number
591 - 491 = 100
100 ÷ 491 = 0.20366598778004075
0.20366598778004075 x 100 = 20.37%