-25.32% is the change from 861 to 643
Calculation steps:
[( 643 - 861 ) ÷ 861] x 100 = -25.32%
Formula
Percentage change = [(643 - 861) / 861] x 100
Subtract the new number by the original number
643 - 861 = -218
-218 ÷ 861 = -0.25319396051103366
-0.25319396051103366 x 100 = -25.32%