-80.87% is the change from 643 to 123
Calculation steps:
[( 123 - 643 ) ÷ 643] x 100 = -80.87%
Formula
Percentage change = [(123 - 643) / 643] x 100
Subtract the new number by the original number
123 - 643 = -520
-520 ÷ 643 = -0.8087091757387247
-0.8087091757387247 x 100 = -80.87%