In the course of doing some data modeling this morning, I found myself confused by the default behavior of sparklines in Excel 2011.
As these small charts are useful in making comparisons, it didn’t makes sense that the axes were different for each sparkline summarizing individual rows in a range.
In the above example, the first data point is the same in both rows and should be scale (note is is larger in the second row). Using the “Automatic” setting in Excel (the default mind you), the vertical axis is set independently for each sparkling.
After fixing the problem using the steps below, you can see the difference in the “Same” column. The first data point is now scale and the graphics are useful for comparison.
On the ribbon (in Excel 2011 for Mac at least), click Charts > Sparklines and click Axes to bring up the the settings below:
On the Vertical tab, select “Same for all sparklines” for both Minimum and Maximum values. Clearly this might be different for different uses and formats of sparklines, but for simple comparisons, it would seem that “Same” should be the default.