Aggregate results of wild-card "include pattern" into a single graph

Hi,
I am building graphs to show stats on a specific website. A single site with 1 domain may have many referers due to the path being different eg, here are 3:

http://a.b.com
http://a.b.com/page1/
http://a.b.com/page2/

So when aggregating by referer.raw I use the 'advanced' option 'include pattern' and I put the following wild-card expression:
.a.b.com.

This regular expression fetches all referers that contain "a.b.com" which is great! BUT, it provides a graph per hit so 3 graphs, 1 for each referer! How can I get the result to be aggregated into a single graph?

Many thanks.