-81.9% is the change from 939 to 170
Calculation steps:
[( 170 - 939 ) ÷ 939] x 100 = -81.9%
Formula
Percentage change = [(170 - 939) / 939] x 100
Subtract the new number by the original number
170 - 939 = -769
-769 ÷ 939 = -0.8189563365282215
-0.8189563365282215 x 100 = -81.9%