Excel help - how do I make an "changing slope" line in Excel?

[SaltyNuts]

I've been making a ton of money in the stock market, but think I can make even more using a slightly revised analytical approach.

To do so, however, I need to be able to graph a "changing slope" line in Excel.

The X axis is stock price. The Y axis is percent shorted let's say. As the stock price goes up, I want the Y axis to go up as well. HOWEVER, I do not want it to be straight line. When the stock price is low and goes up a bit, I want the Y axis to go up a relatively small amount. But the more and more the stock price goes up, I want the Y axis to go up larger amounts over time.

So the result is you have a curved line, rather than a straight line.

Anyone know what function, etc. to use to draw this in Excel? I would guess I would need at least a third data point to input that would help determine the shape of the slope.

Thanks for any help!

 

[IronWing]

Stock derivatives?

 

[SaltyNuts]

Not sure what you are asking or saying IronWing - that is not responsive to my inquiry AT ALL.

 

[z1ggy]

Your explanation of what you want makes no sense to me.

A picture is worth 1000 words.

By the way, if it's not already a metric on Google's stock app or Yahoo's, then it's probably not worth your time because whatever you're trying to accomplish is meaningless.

 

[SaltyNuts]

?!?! It is pretty straight forward. I want a line that curves SLOWLY at first, but the further out you go (on one axis) curves MORE STEEPLY over time. I'm pretty sure there is a name for it. Would draw simple picture but I don't have tools to scan it in and post it and all that.

 

[jman19]

You want something exponential?

 

[IronWing]

Do you want a best fit curve or a line that actually touches all the data points (or a best fit line that touches all the data points)?

 

[jman19]

Do you want a best fit curve or a line that actually touches all the data points (or a best fit line that touches all the data points)?

This

 

[SaltyNuts]

Ah, a line that actually touches the data points. That's why I would think you need the three data points. Is it an "exponential" line as jman19 mentioned? Thanks so much!

 

[deadlyapp]

You need a minimum of 3 data points to draw an exponential curve. Once you increase over 3 points you can draw a polynomial but more than likely you want an exponential curve that is best fit.

 

[SaltyNuts]

Got it. I'll look into how to draw exponential curves in excel - sounds exactly like what I am looking for. Thanks everyone!

 

[IronWing]

Ah, a line that actually touches the data points. That's why I would think you need the three data points. Is it an "exponential" line as jman19 mentioned? Thanks so much!

Insert > Scatter > Scatter with Smooth Lines

This will give you a smoothed line that touches all the data points. It is not a regression curve or an exponential fit line. It merely connects the dots in a smooth fashion.

A regression line uses a statistical analysis of the data to "fit" the line to the points as best it can but likely wouldn't touch any of the points.

 

[SaltyNuts]

Thanks IronWing, will take a look! Much appreciated.

 

[SaltyNuts]

Hmmm, now I'm confused! So first take a straight diagonal line between two points, going from low in the southwest to high in the northeast. Now imagine a third point somewhere in the southeast. I want the line to now run through that third point, and from the southwest point to that third point to be relatively flat, but from that third point to the northeast point to be much steeper. The slope would increase overtime the further to the east you move. Is that an exponential line or regression line? Thanks!

 

[z1ggy]

The fail in this thread is pretty high. Getting out before the week long migraine I have gets worse. Good luck all.

 

[IronWing]

Hmmm, now I'm confused! So first take a straight diagonal line between two points, going from low in the southwest to high in the northeast. Now imagine a third point somewhere in the southeast. I want the line to now run through that third point, and from the southwest point to that third point to be relatively flat, but from that third point to the northeast point to be much steeper. The slope would increase overtime the further to the east you move. Is that an exponential line or regression line? Thanks!

If you want the line to extend past the data you have so that you can make predictions amount future values then you would need to use a regression line. Excel offers a built-in simple linear regression which produces the statistics you would use to build a straight line. I haven't found an exponential fit yet but it may be in there or you may need to find an example spreadsheet on the web. To use regression lines intelligently, you have to understand the underlying statistics. There really is no shortcut. The table of stats that Excel returns for a regression tell you how good the fit is. If you can't interpret the stats you won't know if that really pretty line is garbage.

 

[SaltyNuts]

No IronWing, just need the line to run through the data points, starting at the first one and stopping at the last one. Would that be exponential line? Googling exponential lines they looked to have the increasing slope over time that I am looking for. Thanks!

 

[IronWing]

No IronWing, just need the line to run through the data points, starting at the first one and stopping at the last one. Would that be exponential line? Googling exponential lines they looked to have the increasing slope over time that I am looking for. Thanks!

Then the scatter plot with smooth line should work for you.

 

[SaltyNuts]

Got it. Thanks again!