-90.23% is the change from 839 to 82
Calculation steps:
[( 82 - 839 ) ÷ 839] x 100 = -90.23%
Formula
Percentage change = [(82 - 839) / 839] x 100
Subtract the new number by the original number
82 - 839 = -757
-757 ÷ 839 = -0.902264600715137
-0.902264600715137 x 100 = -90.23%