9.4% is the change from 521 to 570
Calculation steps:
[( 570 - 521 ) ÷ 521] x 100 = 9.4%
Formula
Percentage change = [(570 - 521) / 521] x 100
Subtract the new number by the original number
570 - 521 = 49
49 ÷ 521 = 0.09404990403071017
0.09404990403071017 x 100 = 9.4%