-25.52% is the change from 870 to 648
Calculation steps:
[( 648 - 870 ) ÷ 870] x 100 = -25.52%
Formula
Percentage change = [(648 - 870) / 870] x 100
Subtract the new number by the original number
648 - 870 = -222
-222 ÷ 870 = -0.25517241379310346
-0.25517241379310346 x 100 = -25.52%