-71.2% is the change from 830 to 239
Calculation steps:
[( 239 - 830 ) ÷ 830] x 100 = -71.2%
Formula
Percentage change = [(239 - 830) / 830] x 100
Subtract the new number by the original number
239 - 830 = -591
-591 ÷ 830 = -0.7120481927710843
-0.7120481927710843 x 100 = -71.2%