If you want to increase sales at CoolTShirts.com, would you count on buzzfeed or increase facebook ads? The real question is: should June’s purchase be attributed to buzzfeed or to facebook?

There are two ways of analyzing this:

• First-touch attribution only considers the first utm_source for each customer, which would be buzzfeed in this case. This is a good way of knowing how visitors initially discover a website.
• Last-touch attribution only considers the last utm_source for each customer, which would be facebook in this case. This is a good way of knowing how visitors are drawn back to a website, especially for making a final purchase.

The results can be crucial to improving a company’s marketing and online presence. Most companies analyze both first- and last-touch attribution and display the results separately.