-99.88% is the change from 839 to 1
Calculation steps:
[( 1 - 839 ) ÷ 839] x 100 = -99.88%
Formula
Percentage change = [(1 - 839) / 839] x 100
Subtract the new number by the original number
1 - 839 = -838
-838 ÷ 839 = -0.99880810488677
-0.99880810488677 x 100 = -99.88%