19.5% is the change from 400 to 478
Calculation steps:
[( 478 - 400 ) ÷ 400] x 100 = 19.5%
Formula
Percentage change = [(478 - 400) / 400] x 100
Subtract the new number by the original number
478 - 400 = 78
78 ÷ 400 = 0.195
0.195 x 100 = 19.5%
Example