-16.95% is the change from 991 to 823
Calculation steps:
[( 823 - 991 ) ÷ 991] x 100 = -16.95%
Formula
Percentage change = [(823 - 991) / 991] x 100
Subtract the new number by the original number
823 - 991 = -168
-168 ÷ 991 = -0.16952573158425832
-0.16952573158425832 x 100 = -16.95%