-2.77% is the change from 830 to 807
Calculation steps:
[( 807 - 830 ) ÷ 830] x 100 = -2.77%
Formula
Percentage change = [(807 - 830) / 830] x 100
Subtract the new number by the original number
807 - 830 = -23
-23 ÷ 830 = -0.027710843373493974
-0.027710843373493974 x 100 = -2.77%