Hi Dave,
My name is Dave also. Hope you are having a good day. I am trying to
accomplish a task in Excel and was referred here and to you by Ron
Rosenfeld, while using the Excel Programming News Group. First I will
thank you for your time and efforts, which when I look at what you have
done is already considerable. Then I will confess that it has been a
long time since I studied stats.
I have what is a fairly simple set of data, a Date and an Adj Close*,
which is data assocated with the Dow Jones Averages. The data looks
like this:
Date Adj. Close*
01/03/05 10729.43
12/27/04 10776.13
12/20/04 10661.6
.......More data
The data is graphed and a 6th Degree Polynomial Trend line is added to
the chart.
What I am trying to do is add to the data set is a data point
associated with the 6th Degree Polynomial Trend line, so the data would
look something like this:
Date Adj. Close* Trend
01/03/05 10729.43 10750.20(these are guesses, just for example,
but what I am trying to calculate)
12/27/04 10776.13 10751.23
12/20/04 10661.6 10680.00
.......More data
Like I said, it has been a long time since I have studied stats. I
don't know that it is possible to do this, but it seems that creating a
table that caculates the trend number for the particular Date and Adj.
Close would be possible. I have tried several of the Excel functions
but do not get numbers that approximate the "Trend Numbers." I have
tried:
=LINEST(A2:A314,B2:B314) and get: -.2682
then the formula supplied with the chart:
y = -6E-11^6 + 1E-05^5 - 1.2819^4 + 65247^3 - 2E+09^2 + 3E+13x - 2E+17
and I get some thing like
-445,236,000,000,000,000
I also tried Forecast and Trend, neither of which came close to what
the Trend Line indicated as reasonable. I am at a loss. If you have the
time to shed some light on this, I would appreciate it.

It looks like your function:
Function TLeval(vX, vSheet, vCht, vSeries, vTL)
might do what I am thinking of, but I am not certain. It looks like
part of the code got cut off. I tried to copy it over to word and
figure out what arguments it needs and stuff, but I have not been able
to get through it. Thanks for your time and effort, I hope you have a
good day.

Sincerely,
David Lanman