-67.82% is the change from 870 to 280
Calculation steps:
[( 280 - 870 ) ÷ 870] x 100 = -67.82%
Formula
Percentage change = [(280 - 870) / 870] x 100
Subtract the new number by the original number
280 - 870 = -590
-590 ÷ 870 = -0.6781609195402298
-0.6781609195402298 x 100 = -67.82%