The owners of the Empire State Building like to promote it as the most famous office building in the world.

But the real moneymaker at the 102-story skyscraper is not the 2.7 million square feet of commercial space occupied by tenants like the Federal Deposit Insurance Corporation.

It is the view.

The cramped observation decks on the 86th and 102nd floors are startlingly profitable, especially during the holiday season, when tourists swarm the city.

The decks attract four million visitors a year and generated $60 million in profits in 2010, while the owners made little if any money on the office space, according to newly disclosed documents that offer a rare glimpse at the building’s balance sheet.