-22.77% is the change from 830 to 641
Calculation steps:
[( 641 - 830 ) ÷ 830] x 100 = -22.77%
Formula
Percentage change = [(641 - 830) / 830] x 100
Subtract the new number by the original number
641 - 830 = -189
-189 ÷ 830 = -0.22771084337349398
-0.22771084337349398 x 100 = -22.77%