81.77% is the change from 521 to 947
Calculation steps:
[( 947 - 521 ) ÷ 521] x 100 = 81.77%
Formula
Percentage change = [(947 - 521) / 521] x 100
Subtract the new number by the original number
947 - 521 = 426
426 ÷ 521 = 0.817658349328215
0.817658349328215 x 100 = 81.77%