-25.78% is the change from 861 to 639
Calculation steps:
[( 639 - 861 ) ÷ 861] x 100 = -25.78%
Formula
Percentage change = [(639 - 861) / 861] x 100
Subtract the new number by the original number
639 - 861 = -222
-222 ÷ 861 = -0.2578397212543554
-0.2578397212543554 x 100 = -25.78%