-85% is the change from 500 to 75
Calculation steps:
[( 75 - 500 ) ÷ 500] x 100 = -85%
Formula
Percentage change = [(75 - 500) / 500] x 100
Subtract the new number by the original number
75 - 500 = -425
-425 ÷ 500 = -0.85
-0.85 x 100 = -85%
Example