64.45% is the change from 391 to 643
Calculation steps:
[( 643 - 391 ) ÷ 391] x 100 = 64.45%
Formula
Percentage change = [(643 - 391) / 391] x 100
Subtract the new number by the original number
643 - 391 = 252
252 ÷ 391 = 0.6445012787723785
0.6445012787723785 x 100 = 64.45%