Would you be able to re-post your workbook after saving it as a packaged workbook (.twbx)? As it is now, it does not include your Excel document, so no one will be able to open it. Did you receive a warning when you uploaded?
Hi, Reid. The attached workbook contains a solution, also shown in the image below.
A couple of things that you'll need to think about as you move more into Tableau. Your data is won't be useable to solve this problem in Tableau in the shape that it's in in the example file.You will need to reshape your data. You can use the Tableau Excel addin-in to reshape the data that is explained here. I included an Excel file, too, so you can see the before and after reshaping and to help you get going. Once you get the hang of reshaping, it takes only a few seconds to do.
The second item I noticed is the dates. I recommend using date values that are complete. I'm sure there is a ninja way to get Tableau to recognize Q1 '11 as a date instead of a string. But, in the meantime, I'd use commonly recognizable values for dates such as July 1, 2011. A big advantage is that you'll have more options available to you to explore and visualize your data..
There are many missing values in the data. This accounts for the 25th percentiles being on the axis for some quarters..
Also, these are 25 and 75 percentiles. This video linked here discusses support for percentile aggregations and should get you going.