Excel - Slope/Trend Functions

[jennilein]

Not sure if this is more an excel questions, or basic math - but here goes...

I have several products and a 2-digit number that represents each sales month. I ran a cross tab in access to pull my total sales per month, per product and exported to excel.

Now...my products are in column A, and from D - S are my consecutive sales months (represented by a 2 digit number). I wanted to see if my sales are increasing or decreasing, I used a slope function like this:
=SLOPE(D2:S2,$D$1:$S$1). Would a trend function be better? If so, how does that work? I can't figure out what my "new x's" would be? Any statistical experts out there? I also saw a Growth function - anyone know anything about that one?

Thanks in advance for all your input!

Jennilein

 

[SkipVought]

Jennilein,

If you plotted each row (as y-axis data) against the dates (as x-axis data) and added a LINEAR trendline for any series, the SLOPE of the trendline would be what the SLOPE function calculates for any series.

The TREND function is used to generate a staight line from known x & y values.

What is your objective?



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[jennilein]

My objective is to see if sales are declining or increasing over time.

I already have the information plotted as you described...that's what I used the slope function with. So, I guess I'm on the right track, right?

Thanks.
Jennilein

 

[SkipVought]

Of course, the slope depends on the sample interval. Would you ues ALL the data from the beggining of time or the last lear or 6-months????

You'd get a different answer with each one.

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[sub]
[red]Be advised:[/red]When Viscounts were guillotined just as they were disclosing where their jewels were hidden, it shows to go that you should...
Never hatchet your Counts before they chicken! [/sub]