-17.32% is the change from 993 to 821
Calculation steps:
[( 821 - 993 ) ÷ 993] x 100 = -17.32%
Formula
Percentage change = [(821 - 993) / 993] x 100
Subtract the new number by the original number
821 - 993 = -172
-172 ÷ 993 = -0.1732124874118832
-0.1732124874118832 x 100 = -17.32%