Data was derived from the Thomson/Reuters Science Citation Index and the "Physics" section. They have a high percentage of the citations while publishing a small number of journals.
Snapshot of top Physics Publishers. Data derived from Thomson/Reuters Science Citation Index and the Journal Citation Reports.
Average cost per article was derived from journalprices.com. The APS publishes their journals with very low cost per article.
Note: I am on a rolling position as a library adviser on the APS Publications Oversight Committee.