-79.8% is the change from 609 to 123
Calculation steps:
[( 123 - 609 ) ÷ 609] x 100 = -79.8%
Formula
Percentage change = [(123 - 609) / 609] x 100
Subtract the new number by the original number
123 - 609 = -486
-486 ÷ 609 = -0.7980295566502463
-0.7980295566502463 x 100 = -79.8%