FACTBOX: Facts about New York Mayor Michael Bloomberg

(Reuters) - New York City Mayor Michael Bloomberg was elected to his third four-year term on Tuesday, defeating the city's Democratic Comptroller Bill Thompson in a surprisingly close vote, 51 percent to 46 percent.

Following are some facts about Bloomberg.

* Bloomberg is the founder of the Bloomberg LP news and information company, which competes with Thomson Reuters. He is ranked 17th on the Forbes list of the world's richest people, and is first among New Yorkers, with a net worth of $16 billion.

* Bloomberg, 67, was born in Boston. He is divorced and has two children. His companion, Diana Taylor, is the former New York State Superintendent of Banks.

* As mayor, Bloomberg has won praise for fiscal prudence, the city's 36 percent drop in crime since 2001, and taking over the much-criticized public school system.

* A longtime Democrat, Bloomberg became a Republican to run in 2001, dropped his party registration in 2007 and ran this year on the Republican and Independence party lines. He eked out a victory against Public Advocate Mark Green in 2001 and won a second term in 2005 against former Bronx Borough President Fernando Ferrer by about 20 percentage points.

* Bloomberg would have been ineligible to run for re-election but he pushed a term-limits change through the City Council last year -- extending the limit from two to three terms -- on the grounds that his financial skills and experience were invaluable for guiding the city through hard economic times.

* He already has disclosed spending nearly $90 million of his own money in this year's campaign, making it the most expensive self-financed campaign in U.S. history, and that figure could grow to $110 million to $140 million when all the campaign spending is tallied up. Bloomberg set the previous record when he spent $85 million to win his second term.

(Editing by Ellen Wulfhorst, Daniel Trotta and Will Dunham)