-13.15% is the change from 639 to 555
Calculation steps:
[( 555 - 639 ) ÷ 639] x 100 = -13.15%
Formula
Percentage change = [(555 - 639) / 639] x 100
Subtract the new number by the original number
555 - 639 = -84
-84 ÷ 639 = -0.13145539906103287
-0.13145539906103287 x 100 = -13.15%