-25.52% is the change from 858 to 639
Calculation steps:
[( 639 - 858 ) ÷ 858] x 100 = -25.52%
Formula
Percentage change = [(639 - 858) / 858] x 100
Subtract the new number by the original number
639 - 858 = -219
-219 ÷ 858 = -0.25524475524475526
-0.25524475524475526 x 100 = -25.52%