-2.74% is the change from 838 to 815
Calculation steps:
[( 815 - 838 ) ÷ 838] x 100 = -2.74%
Formula
Percentage change = [(815 - 838) / 838] x 100
Subtract the new number by the original number
815 - 838 = -23
-23 ÷ 838 = -0.027446300715990454
-0.027446300715990454 x 100 = -2.74%