-98.42% is the change from 823 to 13
Calculation steps:
[( 13 - 823 ) ÷ 823] x 100 = -98.42%
Formula
Percentage change = [(13 - 823) / 823] x 100
Subtract the new number by the original number
13 - 823 = -810
-810 ÷ 823 = -0.9842041312272175
-0.9842041312272175 x 100 = -98.42%