-83.39% is the change from 939 to 156
Calculation steps:
[( 156 - 939 ) ÷ 939] x 100 = -83.39%
Formula
Percentage change = [(156 - 939) / 939] x 100
Subtract the new number by the original number
156 - 939 = -783
-783 ÷ 939 = -0.8338658146964856
-0.8338658146964856 x 100 = -83.39%