-80% is the change from 425 to 85
Calculation steps:
[( 85 - 425 ) ÷ 425] x 100 = -80%
Formula
Percentage change = [(85 - 425) / 425] x 100
Subtract the new number by the original number
85 - 425 = -340
-340 ÷ 425 = -0.8
-0.8 x 100 = -80%
Example