64.62% is the change from 390 to 642
Calculation steps:
[( 642 - 390 ) ÷ 390] x 100 = 64.62%
Formula
Percentage change = [(642 - 390) / 390] x 100
Subtract the new number by the original number
642 - 390 = 252
252 ÷ 390 = 0.6461538461538462
0.6461538461538462 x 100 = 64.62%