-0.83% is the change from 847 to 840
Calculation steps:
[( 840 - 847 ) ÷ 847] x 100 = -0.83%
Formula
Percentage change = [(840 - 847) / 847] x 100
Subtract the new number by the original number
840 - 847 = -7
-7 ÷ 847 = -0.008264462809917356
-0.008264462809917356 x 100 = -0.83%