-50.87% is the change from 173 to 85
Calculation steps:
[( 85 - 173 ) ÷ 173] x 100 = -50.87%
Formula
Percentage change = [(85 - 173) / 173] x 100
Subtract the new number by the original number
85 - 173 = -88
-88 ÷ 173 = -0.5086705202312138
-0.5086705202312138 x 100 = -50.87%