-15.64% is the change from 991 to 836
Calculation steps:
[( 836 - 991 ) ÷ 991] x 100 = -15.64%
Formula
Percentage change = [(836 - 991) / 991] x 100
Subtract the new number by the original number
836 - 991 = -155
-155 ÷ 991 = -0.15640766902119072
-0.15640766902119072 x 100 = -15.64%