Examples

To graph sales in each quarter and overlay the sales of each individual printer, specify the graph's data as in “Graphing unit sales of each printer”, but use the following expression in the Series box:

"Total Sales", "@overlay~t" + product

Here is the resulting graph:

The sample graph is titled Printed Sales.  At bottom are legends for Total Sales, which is a shaded column, and for Cosmic, an x, Galactic, an asterisk, and Stellar, a triangle. Three overlay series are plotted as separate lines using the legends for Cosmic, Galactic, and Stellar on top of the four shaded columns that represent total sales of all printers per quarter.

To graph unit sales of printers by quarter and overlay the largest sale made in each quarter, change the Value expression to this:

sum(units for graph), max(units for graph)

Change the Series expression to this:

"Total Sales", "@overlay~tLargets Sale"

Here is the resulting graph:

The sample graph is titled Printer Sales. At bottom are legends. Total Sales is a shaded column and Largest Sale is an x. An overlay series for Largest Sale is plotted as a line connected by x’s on top of the four shaded columns that represent total sales of all printers per quarter.