-79.58% is the change from 671 to 137
Calculation steps:
[( 137 - 671 ) ÷ 671] x 100 = -79.58%
Formula
Percentage change = [(137 - 671) / 671] x 100
Subtract the new number by the original number
137 - 671 = -534
-534 ÷ 671 = -0.7958271236959762
-0.7958271236959762 x 100 = -79.58%