64.43% is the change from 388 to 638
Calculation steps:
[( 638 - 388 ) ÷ 388] x 100 = 64.43%
Formula
Percentage change = [(638 - 388) / 388] x 100
Subtract the new number by the original number
638 - 388 = 250
250 ÷ 388 = 0.6443298969072165
0.6443298969072165 x 100 = 64.43%