-2.8% is the change from 999 to 971
Calculation steps:
[( 971 - 999 ) ÷ 999] x 100 = -2.8%
Formula
Percentage change = [(971 - 999) / 999] x 100
Subtract the new number by the original number
971 - 999 = -28
-28 ÷ 999 = -0.028028028028028028
-0.028028028028028028 x 100 = -2.8%