-17% is the change from 500 to 415
Calculation steps:
[( 415 - 500 ) ÷ 500] x 100 = -17%
Formula
Percentage change = [(415 - 500) / 500] x 100
Subtract the new number by the original number
415 - 500 = -85
-85 ÷ 500 = -0.17
-0.17 x 100 = -17%
Example