-22.86% is the change from 840 to 648
Calculation steps:
[( 648 - 840 ) ÷ 840] x 100 = -22.86%
Formula
Percentage change = [(648 - 840) / 840] x 100
Subtract the new number by the original number
648 - 840 = -192
-192 ÷ 840 = -0.22857142857142856
-0.22857142857142856 x 100 = -22.86%