-83.13% is the change from 830 to 140
Calculation steps:
[( 140 - 830 ) ÷ 830] x 100 = -83.13%
Formula
Percentage change = [(140 - 830) / 830] x 100
Subtract the new number by the original number
140 - 830 = -690
-690 ÷ 830 = -0.8313253012048193
-0.8313253012048193 x 100 = -83.13%