-82.78% is the change from 999 to 172
Calculation steps:
[( 172 - 999 ) ÷ 999] x 100 = -82.78%
Formula
Percentage change = [(172 - 999) / 999] x 100
Subtract the new number by the original number
172 - 999 = -827
-827 ÷ 999 = -0.8278278278278278
-0.8278278278278278 x 100 = -82.78%