-81.91% is the change from 680 to 123
Calculation steps:
[( 123 - 680 ) ÷ 680] x 100 = -81.91%
Formula
Percentage change = [(123 - 680) / 680] x 100
Subtract the new number by the original number
123 - 680 = -557
-557 ÷ 680 = -0.8191176470588235
-0.8191176470588235 x 100 = -81.91%