-69.17% is the change from 399 to 123
Calculation steps:
[( 123 - 399 ) ÷ 399] x 100 = -69.17%
Formula
Percentage change = [(123 - 399) / 399] x 100
Subtract the new number by the original number
123 - 399 = -276
-276 ÷ 399 = -0.6917293233082706
-0.6917293233082706 x 100 = -69.17%