How is pch calculated?

[plowel]

How is pch calculated in Eviews? is it [x(t)-x(t-1)]/x(t-1)?

What would happen if we are at boundary conditions, such as x(t-1) is negative, or both x(t) and x(t-1) are negative?

Thank you in advance.

[EViews Gareth]

If you do:

Code: Select all

create u 100
series x=nrnd
show @pch(x) ((x-x(-1))/x(-1))


You'll see they give the same results.

You'll also see that negatives are not handled in any special way.