-99.52% is the change from 830 to 4
Calculation steps:
[( 4 - 830 ) ÷ 830] x 100 = -99.52%
Formula
Percentage change = [(4 - 830) / 830] x 100
Subtract the new number by the original number
4 - 830 = -826
-826 ÷ 830 = -0.9951807228915662
-0.9951807228915662 x 100 = -99.52%