667.5% is the change from 40 to 307
Calculation steps:
[( 307 - 40 ) ÷ 40] x 100 = 667.5%
Formula
Percentage change = [(307 - 40) / 40] x 100
Subtract the new number by the original number
307 - 40 = 267
267 ÷ 40 = 6.675
6.675 x 100 = 667.5%
Example