-48.82% is the change from 170 to 87
Calculation steps:
[( 87 - 170 ) ÷ 170] x 100 = -48.82%
Formula
Percentage change = [(87 - 170) / 170] x 100
Subtract the new number by the original number
87 - 170 = -83
-83 ÷ 170 = -0.48823529411764705
-0.48823529411764705 x 100 = -48.82%