-86.9% is the change from 939 to 123
Calculation steps:
[( 123 - 939 ) ÷ 939] x 100 = -86.9%
Formula
Percentage change = [(123 - 939) / 939] x 100
Subtract the new number by the original number
123 - 939 = -816
-816 ÷ 939 = -0.8690095846645367
-0.8690095846645367 x 100 = -86.9%