I have a line overlaid on some bars in a pivot chart in excel, but I want the line to be stepped instead of curved. How can I accomplish this?

For anything to do with charting in Excel, @Jon Peltier is the man but a line chart that looks as on the left below can be converted into a stepped chart as on the right without calculation quite simply by repeating the Xaxis values (in order) and inserting duplicate values with an offset as shown: Though I admit I don't really know whether this is what you would like. 


Error bars can be quite useful, even if you do not know what they are fully for; in most cases, they can be used to show variations in data; but when used creatively, they can turn any line into a stepped line. Here's a writeup of it: Step Charts in Microsoft Excel Essentially, your adding error bars to a range of data, and then just hiding all but the error bars; turns out quite nicely, if you follow the instructions. There is another method; however, that involves adding extra data to your chart; or, adding extra calculations to the chart, to 'simulate' data. 

