-91.05% is the change from 939 to 84
Calculation steps:
[( 84 - 939 ) ÷ 939] x 100 = -91.05%
Formula
Percentage change = [(84 - 939) / 939] x 100
Subtract the new number by the original number
84 - 939 = -855
-855 ÷ 939 = -0.9105431309904153
-0.9105431309904153 x 100 = -91.05%