-0.12% is the change from 830 to 829
Calculation steps:
[( 829 - 830 ) ÷ 830] x 100 = -0.12%
Formula
Percentage change = [(829 - 830) / 830] x 100
Subtract the new number by the original number
829 - 830 = -1
-1 ÷ 830 = -0.0012048192771084338
-0.0012048192771084338 x 100 = -0.12%