8.15% is the change from 491 to 531
Calculation steps:
[( 531 - 491 ) ÷ 491] x 100 = 8.15%
Formula
Percentage change = [(531 - 491) / 491] x 100
Subtract the new number by the original number
531 - 491 = 40
40 ÷ 491 = 0.0814663951120163
0.0814663951120163 x 100 = 8.15%