-40.48% is the change from 830 to 494
Calculation steps:
[( 494 - 830 ) ÷ 830] x 100 = -40.48%
Formula
Percentage change = [(494 - 830) / 830] x 100
Subtract the new number by the original number
494 - 830 = -336
-336 ÷ 830 = -0.40481927710843374
-0.40481927710843374 x 100 = -40.48%