71.13% is the change from 388 to 664
Calculation steps:
[( 664 - 388 ) ÷ 388] x 100 = 71.13%
Formula
Percentage change = [(664 - 388) / 388] x 100
Subtract the new number by the original number
664 - 388 = 276
276 ÷ 388 = 0.711340206185567
0.711340206185567 x 100 = 71.13%