-20.32% is the change from 802 to 639
Calculation steps:
[( 639 - 802 ) ÷ 802] x 100 = -20.32%
Formula
Percentage change = [(639 - 802) / 802] x 100
Subtract the new number by the original number
639 - 802 = -163
-163 ÷ 802 = -0.20324189526184538
-0.20324189526184538 x 100 = -20.32%