-82.89% is the change from 830 to 142
Calculation steps:
[( 142 - 830 ) ÷ 830] x 100 = -82.89%
Formula
Percentage change = [(142 - 830) / 830] x 100
Subtract the new number by the original number
142 - 830 = -688
-688 ÷ 830 = -0.8289156626506025
-0.8289156626506025 x 100 = -82.89%