I have a bubble plot in which each axis is a different, discrete list of mutually-exclusive text descriptors for the data (for instance, imagine a table of vehicle attributes where the X axis has different vehicle size classifications like subcompact, compact, sedan, etc. and the Y axis has cost descriptors such as bargain, relatively inexpensive, average cost, relatively expensive, and uber-expensive). I want the size of each bubble to be proportional to the total number of times that that combination of X and Y values appears in my data table. How do I do this? Thanks.