-84.98% is the change from 639 to 96
Calculation steps:
[( 96 - 639 ) ÷ 639] x 100 = -84.98%
Formula
Percentage change = [(96 - 639) / 639] x 100
Subtract the new number by the original number
96 - 639 = -543
-543 ÷ 639 = -0.8497652582159625
-0.8497652582159625 x 100 = -84.98%