-89.75% is the change from 839 to 86
Calculation steps:
[( 86 - 839 ) ÷ 839] x 100 = -89.75%
Formula
Percentage change = [(86 - 839) / 839] x 100
Subtract the new number by the original number
86 - 839 = -753
-753 ÷ 839 = -0.8974970202622169
-0.8974970202622169 x 100 = -89.75%