-64.6% is the change from 870 to 308
Calculation steps:
[( 308 - 870 ) ÷ 870] x 100 = -64.6%
Formula
Percentage change = [(308 - 870) / 870] x 100
Subtract the new number by the original number
308 - 870 = -562
-562 ÷ 870 = -0.6459770114942529
-0.6459770114942529 x 100 = -64.6%