-3.01% is the change from 897 to 870
Calculation steps:
[( 870 - 897 ) ÷ 897] x 100 = -3.01%
Formula
Percentage change = [(870 - 897) / 897] x 100
Subtract the new number by the original number
870 - 897 = -27
-27 ÷ 897 = -0.030100334448160536
-0.030100334448160536 x 100 = -3.01%