31.7% is the change from 388 to 511
Calculation steps:
[( 511 - 388 ) ÷ 388] x 100 = 31.7%
Formula
Percentage change = [(511 - 388) / 388] x 100
Subtract the new number by the original number
511 - 388 = 123
123 ÷ 388 = 0.3170103092783505
0.3170103092783505 x 100 = 31.7%