-98.77% is the change from 81 to 1
Calculation steps:
[( 1 - 81 ) ÷ 81] x 100 = -98.77%
Formula
Percentage change = [(1 - 81) / 81] x 100
Subtract the new number by the original number
1 - 81 = -80
-80 ÷ 81 = -0.9876543209876543
-0.9876543209876543 x 100 = -98.77%