software

Hi all,

I'm messing around with the trend line function in excel. I see there
are 6 different types of trend/regression types:

- Linear
- Logarithmic
- Polynomial
- Power
- Exponential
- Moving AverageI have a list with 30 data points that I would like to plot on chart
with the different trend/regression lines. I notice that the Power and
Exponential options are greyed out, so that I can not choose them. Is
this because 2 of the 30 numbers are negative?

Thanks!--
deacs
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deacs's Profile: www.excelforum.com/member.php...foamp;userid=2321
View this thread: www.excelforum.com/showthread...hreadid=511723That is correct
See also www.stfx.ca/people/bliengme/E...Polynomial.htm
--
Bernard V Liengme
www.stfx.ca/people/bliengme
remove caps from email

quot;deacsquot; gt; wrote in
message ...
gt;
gt; Hi all,
gt;
gt; I'm messing around with the trend line function in excel. I see there
gt; are 6 different types of trend/regression types:
gt;
gt; - Linear
gt; - Logarithmic
gt; - Polynomial
gt; - Power
gt; - Exponential
gt; - Moving Average
gt;
gt;
gt; I have a list with 30 data points that I would like to plot on chart
gt; with the different trend/regression lines. I notice that the Power and
gt; Exponential options are greyed out, so that I can not choose them. Is
gt; this because 2 of the 30 numbers are negative?
gt;
gt; Thanks!
gt;
gt;
gt; --
gt; deacs
gt; ------------------------------------------------------------------------
gt; deacs's Profile:
gt; www.excelforum.com/member.php...foamp;userid=2321
gt; View this thread: www.excelforum.com/showthread...hreadid=511723
gt;

Thanks for the reply. Is there a way around this, so that I can plot the
power and exponential lines? Must I remove the negative numbers?

The data points I have represent monthly costs and I would like to make
projections based off of the raw numbers as reference points with other
bottoms up projections. The months with negative numbers are months
when there were returns within this cost category.

Thanks again for your help.--
deacs
------------------------------------------------------------------------
deacs's Profile: www.excelforum.com/member.php...foamp;userid=2321
View this thread: www.excelforum.com/showthread...hreadid=511723On Mon, 13 Feb 2006 09:34:28 -0600, deacs
gt; wrote:

gt;
gt; Thanks for the reply. Is there a way around this, so that I can plot the
gt; power and exponential lines? Must I remove the negative numbers?
gt;
gt; The data points I have represent monthly costs and I would like to make
gt; projections based off of the raw numbers as reference points with other
gt; bottoms up projections. The months with negative numbers are months
gt; when there were returns within this cost category.
gt;
gt; Thanks again for your help.One way, although a bit clumsy, would be to add a constant to each number,
so that they are all positive. Plot your trend using whatever function you
choose, and then subtract the same constant from any projection that you
derive from the trend.