-76.47% is the change from 85 to 20
Calculation steps:
[( 20 - 85 ) ÷ 85] x 100 = -76.47%
Formula
Percentage change = [(20 - 85) / 85] x 100
Subtract the new number by the original number
20 - 85 = -65
-65 ÷ 85 = -0.7647058823529411
-0.7647058823529411 x 100 = -76.47%