287.5% is the change from 40 to 155
Calculation steps:
[( 155 - 40 ) ÷ 40] x 100 = 287.5%
Formula
Percentage change = [(155 - 40) / 40] x 100
Subtract the new number by the original number
155 - 40 = 115
115 ÷ 40 = 2.875
2.875 x 100 = 287.5%
Example