How do I change the length of a linear trend line?

[boalsjr]

I have a chart which plots several different data series in a simple linear graph. Each of these series has a linear trend line. All these trend lines simply match the length of the plot line.

However, for one particular series, the trend line extends the entire length of the graph. I checked the Format->Trendline window on all the other lines and they show the "Backwards" box grayed out. But on this one particular trend line that runs the length of the graph, it's not. Everything else matches the other (short) trend lines.

The Options tab has:

Custom title
Forecast: Forward = 0 Backward = 0
Set intercept, Display equation, Display R-squared value are all NOT checked.

When the linear trend line extends the length of the chart, it compresses the scale and makes the whole chart look funny.

Has anybody run into this problem? If so, how do I fix it?

Thanks,

Jon

 

[macajm]

are you sure that there is not a stray data point which would plot "off the graph"? for this series?
This could create the effect I think you describe.

 

[boalsjr]

I checked the data thoroughly, based on your suggestion. I cannot find any stray points. Any other suggestions?

Thanks.

 

[macajm]

One other way I could create a similar problem is by having blank cells included in a data series - have you checked for this?

I assume you have tried deleting and re-creating the particular data series definition and its associated trendline just in case there is something oddball in the definition.

Otherwise - You've got me stumped!
A second-rate workaround maybe to force the Chart scale (ie uncheck the auto scaling) to prevent the shrinkage of the chart data. - but that doesn't find the root cause of your problem.