-5.17% is the change from 870 to 825
Calculation steps:
[( 825 - 870 ) ÷ 870] x 100 = -5.17%
Formula
Percentage change = [(825 - 870) / 870] x 100
Subtract the new number by the original number
825 - 870 = -45
-45 ÷ 870 = -0.05172413793103448
-0.05172413793103448 x 100 = -5.17%