-99.09% is the change from 993 to 9
Calculation steps:
[( 9 - 993 ) ÷ 993] x 100 = -99.09%
Formula
Percentage change = [(9 - 993) / 993] x 100
Subtract the new number by the original number
9 - 993 = -984
-984 ÷ 993 = -0.9909365558912386
-0.9909365558912386 x 100 = -99.09%