-82.78% is the change from 993 to 171
Calculation steps:
[( 171 - 993 ) ÷ 993] x 100 = -82.78%
Formula
Percentage change = [(171 - 993) / 993] x 100
Subtract the new number by the original number
171 - 993 = -822
-822 ÷ 993 = -0.8277945619335347
-0.8277945619335347 x 100 = -82.78%