662.5% is the change from 40 to 305
Calculation steps:
[( 305 - 40 ) ÷ 40] x 100 = 662.5%
Formula
Percentage change = [(305 - 40) / 40] x 100
Subtract the new number by the original number
305 - 40 = 265
265 ÷ 40 = 6.625
6.625 x 100 = 662.5%
Example