-24.97% is the change from 857 to 643
Calculation steps:
[( 643 - 857 ) ÷ 857] x 100 = -24.97%
Formula
Percentage change = [(643 - 857) / 857] x 100
Subtract the new number by the original number
643 - 857 = -214
-214 ÷ 857 = -0.24970828471411902
-0.24970828471411902 x 100 = -24.97%