Displaying Trend Lines (Revision #21)

Trend Lines are straight lines that connect two or more points and then extend into the future to assist in detecting and predicting trends in time-series data. To display Trend Lines select [Analysis > Show Trend Lines]. Trend Lines display as black lines overlaid on the current view and are dashed when shown over Line Charts and solid when shown over bar charts to prevent confusing them with original chart content. You can also edit Trend Line Options with [Analysis > Trend Lines > Edit Trend Lines...] when [Analysis > Trend Lines > Show Trend Lines] is enabled. 

Once a Trend Line or Lines are displayed you can view slope and y-intercept for all the displayed Trend Lines by selecting [Analysis > Trend Lines > Describe Trend Model...].

If there are multiple lines, it is possible to show individual Trend Lines per line color by selecting [Analysis > Trend Lines > Edit Trend Lines...> Allow a trend line per color].

Once [Allow a trend Line per color] is enabled in the Trend Options dialog, each Trend Line will have a dashed line of the same color as the line it is trending to make identifying them easier.

If Trend Line Per Color is enabled for a Multi Line Chart, selecting [Analysis > Trend Lines > Describe Trend Model...] will produce Trend Line Details for every Trend Line visible in your chart. 

Edit Trend Line Options

You can select Trend Line options by choosing [Analysis > Trend Lines > Edit Trend Lines...] which launches the Trend Line Options dialog.

From this dialog you can select the Trend Line Model Type as:

• Linear
• Logarithmic
• Exponential
• Polynomial, degree (and choose the value for degree)

Options within the Trend Line Options dialog allow for

• including fields as factors (with the Dimensions listed from your decks)
• enabling/disabling trend line per color
• showing confidence bands
• forcing y-intercept to zero.