-17.12% is the change from 999 to 828
Calculation steps:
[( 828 - 999 ) ÷ 999] x 100 = -17.12%
Formula
Percentage change = [(828 - 999) / 999] x 100
Subtract the new number by the original number
828 - 999 = -171
-171 ÷ 999 = -0.17117117117117117
-0.17117117117117117 x 100 = -17.12%