OKLAHOMA CITY (AP) — Oklahoma continues to far outpace other states on the number of tribal gambling facilities, leading to more than $3.7 billion in gambling revenue in 2012, according to a new national study released Wednesday.

Casino City's Indian Gaming Industry Report shows that Indian casino gambling revenue increased 7 percent from 2011 to 2012 in Oklahoma. The report by economist Alan Meister said 33 tribes operated 118 facilities in 2012, though a large number of those were somewhat small facilities including travel centers and convenience stores. Oklahoma is second in the nation to California in the number of tribes with gambling facilities, but the Sooner State has almost double the number of facilities compared to California. Oklahoma was also second to California in overall Indian casino gambling revenue in 2012.

Sheila Morago, executive director of the Oklahoma Indian Gaming Association, said she was not surprised by the results of the study. She said that even during the recession, Oklahoma's tribal gambling revenue fared better than other states.

"A lot of it has to do with being surrounded by states that don't have gaming," she said. Another factor, she said, is that Oklahoma has a healthy economy and residents still have disposal income to spend on leisure activities.

"It's like any other entertainment option," she said.

Nationally, tribal gambling revenue grew more slowly in 2012 than in 2011. But it still increased by 2 percent, bringing Indian casino gambling revenue to an all-time high of $28.1 billion. Non-gambling revenue, which includes the money patrons spend on food and beverages, lodging, shopping and entertainment at Indian gambling facilities, grew nearly 3 percent nationally in 2012, from $3.3 billion to $3.4 billion. In Oklahoma, non-gambling revenue grew 3.4 percent to $510 million.

Eleven new facilities opened across the country in 2012, including five in Oklahoma.

The total number of gambling machines in the state increased about 7 percent to more than 68,000 in 2012, the report said. The number of table games increased about 8 percent to 813.

Of the more than 68,000 gambling machines, about 58 percent of them were Class III games such as slot machines. Class III games were first allowed in Oklahoma in 2005, and tribes must pay fees to the state to operate them. This is the fourth straight year that there has been a decrease in Class III games as a percentage of total machines, according to the report.