-20.24% is the change from 830 to 662
Calculation steps:
[( 662 - 830 ) ÷ 830] x 100 = -20.24%
Formula
Percentage change = [(662 - 830) / 830] x 100
Subtract the new number by the original number
662 - 830 = -168
-168 ÷ 830 = -0.20240963855421687
-0.20240963855421687 x 100 = -20.24%