-75% is the change from 500 to 125
Calculation steps:
[( 125 - 500 ) ÷ 500] x 100 = -75%
Formula
Percentage change = [(125 - 500) / 500] x 100
Subtract the new number by the original number
125 - 500 = -375
-375 ÷ 500 = -0.75
-0.75 x 100 = -75%
Example