-6.73% is the change from 639 to 596
Calculation steps:
[( 596 - 639 ) ÷ 639] x 100 = -6.73%
Formula
Percentage change = [(596 - 639) / 639] x 100
Subtract the new number by the original number
596 - 639 = -43
-43 ÷ 639 = -0.06729264475743349
-0.06729264475743349 x 100 = -6.73%