There is a special kind of Classifications called Numeric Classifications, as the name implies, these can be used to tie numeric data to Classifications. If you think of Classifications as being smart, then Numeric Classifications are übersmart. Numeric classifications are like special calculated metrics, where the classification data you provide becomes part of the calculation.
A Numeric Classefication is what could be used to calculate the cost of a campaign based on a click price and the existing Click-through metric.

But, beware, there are a few things that are nice to now before you get started on Numeric Classifications.

• It appears to be possible to delete a Numeric Classification, but it is not, the delete function is badly broken and will just show you a blank page when trying to use it.
• If You want to create more than one Numeric Classification on a variable you can’t use SiteCatalyst 14 for the job, switch to SiteCatalyst 13.5 where the feature isn’t broken.
• Not even Clientcare has the tools needed to delete a Numeric Classification, It’s a job for Omniture Engineering and it’ll take around a week to complete, so for testing purposes, I would recommend you create yourself a throw-away report suite.

Oh by the way, one last thing, the metrics created by Numeric Classifications are not working on any of our report suites, whenever I add one of those metrics, it effectively prevents my reports from loading.