-98.77% is the change from 810 to 10
Calculation steps:
[( 10 - 810 ) ÷ 810] x 100 = -98.77%
Formula
Percentage change = [(10 - 810) / 810] x 100
Subtract the new number by the original number
10 - 810 = -800
-800 ÷ 810 = -0.9876543209876543
-0.9876543209876543 x 100 = -98.77%