912.5% is the change from 40 to 405
Calculation steps:
[( 405 - 40 ) ÷ 40] x 100 = 912.5%
Formula
Percentage change = [(405 - 40) / 40] x 100
Subtract the new number by the original number
405 - 40 = 365
365 ÷ 40 = 9.125
9.125 x 100 = 912.5%
Example