90.6% is the change from 521 to 993
Calculation steps:
[( 993 - 521 ) ÷ 521] x 100 = 90.6%
Formula
Percentage change = [(993 - 521) / 521] x 100
Subtract the new number by the original number
993 - 521 = 472
472 ÷ 521 = 0.9059500959692899
0.9059500959692899 x 100 = 90.6%