-1.91% is the change from 836 to 820
Calculation steps:
[( 820 - 836 ) ÷ 836] x 100 = -1.91%
Formula
Percentage change = [(820 - 836) / 836] x 100
Subtract the new number by the original number
820 - 836 = -16
-16 ÷ 836 = -0.019138755980861243
-0.019138755980861243 x 100 = -1.91%