30.67% is the change from 388 to 507
Calculation steps:
[( 507 - 388 ) ÷ 388] x 100 = 30.67%
Formula
Percentage change = [(507 - 388) / 388] x 100
Subtract the new number by the original number
507 - 388 = 119
119 ÷ 388 = 0.30670103092783507
0.30670103092783507 x 100 = 30.67%