-97.68% is the change from 820 to 19
Calculation steps:
[( 19 - 820 ) ÷ 820] x 100 = -97.68%
Formula
Percentage change = [(19 - 820) / 820] x 100
Subtract the new number by the original number
19 - 820 = -801
-801 ÷ 820 = -0.9768292682926829
-0.9768292682926829 x 100 = -97.68%