17.5% is the change from 520 to 611
Calculation steps:
[( 611 - 520 ) ÷ 520] x 100 = 17.5%
Formula
Percentage change = [(611 - 520) / 520] x 100
Subtract the new number by the original number
611 - 520 = 91
91 ÷ 520 = 0.175
0.175 x 100 = 17.5%
Example