39.5% is the change from 400 to 558
Calculation steps:
[( 558 - 400 ) ÷ 400] x 100 = 39.5%
Formula
Percentage change = [(558 - 400) / 400] x 100
Subtract the new number by the original number
558 - 400 = 158
158 ÷ 400 = 0.395
0.395 x 100 = 39.5%
Example