20.51% is the change from 390 to 470
Calculation steps:
[( 470 - 390 ) ÷ 390] x 100 = 20.51%
Formula
Percentage change = [(470 - 390) / 390] x 100
Subtract the new number by the original number
470 - 390 = 80
80 ÷ 390 = 0.20512820512820512
0.20512820512820512 x 100 = 20.51%