Extend a Trendline in Excel

When dealing with Excel Charts, there are so many ways in which you can manipulate them, so that is almost unreal to expect someone to know all the hacks and tricks to it.

In the example below, we will present one of the useful things that you can do in the chart, and that is to extend a trendline.

Extend a Trendline in Excel

We will use a linear trendline for our example, although the same approach is used regardless of the trendline type. Our chart will be created from the following table of Xs and Ys:

Chart

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To create a chart, we will select our data and go to Insert >> Charts >> Recommended Charts:

Graphical user interface, application, Word

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On the window that appears, we will choose the third option, which refers to a Scatter Chart:

Chart, line chart

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Once we click OK, we will have the same chart created as in the picture above. When we double-click on the trendline in the chart (or right-click on it and choose Format Trendline) we will get the window on the right side where we will see the Trendline Options. In this window, when we scroll down we will see the Forecast option:

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A forecast is set to 0 once the chart is created (both for forward and backward). We changed it to 1, and our chart will immediately be changed in a way that we will have our trendline extended for the forecasted figures:

Chart, line chart

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In this particular Chart Design, the forecast will be a little thinner, but we can always change the design. The important thing is that we extend the trendline with the forecast option.

Tomasz Decker is an Excel specialist, skilled in data analysis and financial modeling.