-8.1% is the change from 839 to 771
Calculation steps:
[( 771 - 839 ) ÷ 839] x 100 = -8.1%
Formula
Percentage change = [(771 - 839) / 839] x 100
Subtract the new number by the original number
771 - 839 = -68
-68 ÷ 839 = -0.08104886769964244
-0.08104886769964244 x 100 = -8.1%