-81.42% is the change from 662 to 123
Calculation steps:
[( 123 - 662 ) ÷ 662] x 100 = -81.42%
Formula
Percentage change = [(123 - 662) / 662] x 100
Subtract the new number by the original number
123 - 662 = -539
-539 ÷ 662 = -0.8141993957703928
-0.8141993957703928 x 100 = -81.42%