FACTBOX: Facts about UK's Northern Rock

(Reuters) - British bank Northern Rock was nationalized on Sunday after the government said offers for the troubled lender were not good enough.

The following are some facts on the bank.

* Northern Rock was formed in 1965 as a merger of the Northern Counties Permanent Building Society, established back in 1850, and Rock Building Society.

By the time it scrapped its building society status and listed in 1997, it was an amalgamation of 53 societies.

* Based in Newcastle, in Britain's northeast, Northern Rock is the country's fifth largest mortgage lender, accounting for one in 13 UK home loans.

* The bank has just 76 branches and employs just over 6,000 staff.

* Before the run on the bank in September, it had around 1.4 million savers, some 800,000 mortgage customers and assets totaling 113.5 billion pounds ($223.1 billion).

* It was the first run on a British bank for more than 140 years and the bank is the first to be nationalized since the 1970s.

* The government has loaned Northern Rock around 25 billion pounds to prop it up.

* The bank uses four sources for funding. As of September 2007 they were: Retail 24.4 billion pounds (23 percent of total), Securitization 45.7 billion pounds (43.5 percent), Non-retail 27 billion pounds (25.5 percent), Covered bonds 8.1 billion pounds (8 percent).

* Northern Rock is primarily a lender to "prime" borrowers. Only 20 percent of its loans are to first-time borrowers, meaning the bulk of its borrowers had proven payment track records. It had an average loan-to-value ratio of 78 percent in the first half of 2007, with 81 percent of mortgages at a ratio above 90 percent.

It originates "sub prime" and self-certified home loans for Lehman Brothers.

* On listing, the bank set up the Northern Rock Foundation, a charity which receives around 5 percent of the bank's profit.

* Northern Rock sponsors a string of local sports teams, including Premier League soccer club Newcastle United and rugby side Newcastle Falcons.

(Writing by Marc Jones; Editing by Catherine Evans)