-82.93% is the change from 123 to 21
Calculation steps:
[( 21 - 123 ) ÷ 123] x 100 = -82.93%
Formula
Percentage change = [(21 - 123) / 123] x 100
Subtract the new number by the original number
21 - 123 = -102
-102 ÷ 123 = -0.8292682926829268
-0.8292682926829268 x 100 = -82.93%