-55.56% is the change from 639 to 284
Calculation steps:
[( 284 - 639 ) ÷ 639] x 100 = -55.56%
Formula
Percentage change = [(284 - 639) / 639] x 100
Subtract the new number by the original number
284 - 639 = -355
-355 ÷ 639 = -0.5555555555555556
-0.5555555555555556 x 100 = -55.56%