Chart of the Month – May 2009 – Stair-Step Line Chart
This "line" chart is superior to other line charts when showing this type of comparison. The stair steps give a clearer accounting of levels that are maintained over periods of time and change abruptly due to an event. Other line charts show slanted trend lines, which is an inaccurate depiction of events.
These line charts are actually developed on scatter chart templates. The sprites are eliminated and lines are added. There is a very specific way that data needs to be inserted into the worksheet.
Below are the PowerPoint 2003 and PowerPoint 2007 worksheets. The PowerPoint 2003 worksheet is scrolled down and does not show lines 1 and 2, but they are the same as what is shown in PowerPoint 2007 worksheet.
As you can see, the data is entered into the worksheets in exactly the same way for PowerPoint 2003 (Microsoft Graph) and PowerPoint 2007 (Excel). Both only need to have the X axis values entered once – the columns labeled Y axis in the worksheets and all subsequent columns contain the data for each line.
You may need to adjust the scale on the axes to achieve the spans you need. But this is handled in the same manner as all data-driven charts (no special instructions).
Please note that the X and Y axes can be any units you choose. You are not limited to the units shown in this example. Any plottable values can be used as units for the axes. Click here to go to the scatter chart series (which is available to subscribers only).