-99.9% is the change from 987 to 1
Calculation steps:
[( 1 - 987 ) ÷ 987] x 100 = -99.9%
Formula
Percentage change = [(1 - 987) / 987] x 100
Subtract the new number by the original number
1 - 987 = -986
-986 ÷ 987 = -0.9989868287740629
-0.9989868287740629 x 100 = -99.9%