-83.28% is the change from 993 to 166
Calculation steps:
[( 166 - 993 ) ÷ 993] x 100 = -83.28%
Formula
Percentage change = [(166 - 993) / 993] x 100
Subtract the new number by the original number
166 - 993 = -827
-827 ÷ 993 = -0.8328298086606244
-0.8328298086606244 x 100 = -83.28%