91.2% is the change from 250 to 478
Calculation steps:
[( 478 - 250 ) ÷ 250] x 100 = 91.2%
Formula
Percentage change = [(478 - 250) / 250] x 100
Subtract the new number by the original number
478 - 250 = 228
228 ÷ 250 = 0.912
0.912 x 100 = 91.2%
Example