-40.35% is the change from 285 to 170
Calculation steps:
[( 170 - 285 ) ÷ 285] x 100 = -40.35%
Formula
Percentage change = [(170 - 285) / 285] x 100
Subtract the new number by the original number
170 - 285 = -115
-115 ÷ 285 = -0.40350877192982454
-0.40350877192982454 x 100 = -40.35%