What are the top rental car companies in the US?

For 2013, in terms of fleet size, office locations, and revenue, the top 3 companies in the United States are:

Enterprise Holdings (includes Enterprise, Alamo, National)

- 979,370 cars in service

- 6,045 US locations

- revenue $ 11,900,000,000 (in 2013)

Hertz (includes Dollar, Thrifty)

- 488,000 cars in service

- 5,900 US locations

- revenue $ 6,300,000,000 (in 2013)

Avis Budget Group (includes Avis, Zipcar, Payless)

- 344,000 cars in service

- 3,100 US locations

- revenue $ 5,200,000,000 (in 2013)

(source http://www.autorentalnews.com/fileviewer/1897.aspx)

As you can see, Enterprise is by far the largest in America. I work for Enterprise, and when I was hired I was told that Enterprise is the single largest buyer of new cars in the US annually.

Another interesting detail: Enterprise is privately held, and all locations are corporate (no franchises).