68.46% is the change from 390 to 657
Calculation steps:
[( 657 - 390 ) ÷ 390] x 100 = 68.46%
Formula
Percentage change = [(657 - 390) / 390] x 100
Subtract the new number by the original number
657 - 390 = 267
267 ÷ 390 = 0.6846153846153846
0.6846153846153846 x 100 = 68.46%