Plot a line on a line chart

[RICKDM]

I have created a table that consists of 5 columns. Column 1 is "Date", and columns 2-5 are various types of readings, which are my data. I have a "total row" at the bottom of my table, which averages all the data from each column. I have plotted the data (1 line chart for each column - 4 line charts total), and now I want to plot the "total row" (average) on the same chart, to appear as a straight line. Is there a way to do this without creating a bunch of data points to illustrate the average line? I just want one point (the average for each column), but I want it to appear as a straight line.

Thanks

 

[Steve=True]

Here are some sample files with step-by-step instructions:

http://www.andypope.info/charts/averageline.htm

Steve=True
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