-76.88% is the change from 999 to 231
Calculation steps:
[( 231 - 999 ) ÷ 999] x 100 = -76.88%
Formula
Percentage change = [(231 - 999) / 999] x 100
Subtract the new number by the original number
231 - 999 = -768
-768 ÷ 999 = -0.7687687687687688
-0.7687687687687688 x 100 = -76.88%