-71.15% is the change from 870 to 251
Calculation steps:
[( 251 - 870 ) ÷ 870] x 100 = -71.15%
Formula
Percentage change = [(251 - 870) / 870] x 100
Subtract the new number by the original number
251 - 870 = -619
-619 ÷ 870 = -0.7114942528735633
-0.7114942528735633 x 100 = -71.15%