-79.91% is the change from 687 to 138
Calculation steps:
[( 138 - 687 ) ÷ 687] x 100 = -79.91%
Formula
Percentage change = [(138 - 687) / 687] x 100
Subtract the new number by the original number
138 - 687 = -549
-549 ÷ 687 = -0.7991266375545851
-0.7991266375545851 x 100 = -79.91%