17.35% is the change from 340 to 399
Calculation steps:
[( 399 - 340 ) ÷ 340] x 100 = 17.35%
Formula
Percentage change = [(399 - 340) / 340] x 100
Subtract the new number by the original number
399 - 340 = 59
59 ÷ 340 = 0.17352941176470588
0.17352941176470588 x 100 = 17.35%