-97.1% is the change from 999 to 29
Calculation steps:
[( 29 - 999 ) ÷ 999] x 100 = -97.1%
Formula
Percentage change = [(29 - 999) / 999] x 100
Subtract the new number by the original number
29 - 999 = -970
-970 ÷ 999 = -0.970970970970971
-0.970970970970971 x 100 = -97.1%