BISMARCK - Tourism might conjure images of Theodore Roosevelt National Park in western North Dakota, but that's not the only thing bringing people here - and all together, it's adding up to big business.
A new research study commissioned by North Dakota Tourism found 21.9 million people visited the state in 2015 and spent $3.1 billion.
That's equivalent to everyone from Minnesota, Missouri, Oklahoma, Wisconsin and Wyoming visiting the Peace Garden State, according to Philadelphia-based firm Tourism Economics that conducted the study.
The figure might seem high, but Sara Otte Coleman, director of the North Dakota Department of Commerce's Tourism Division, said it's an accurate count. The number of visitors includes business and leisure travelers, day trips, people coming to Fargo for a concert at the Fargodome and traditional tourists.
It's a sum of the "person-trips" that happened in 2015, but the study didn't count routine trips, such as work commutes.
An evaluation commissioned by Explore Minnesota found tourism and travel in the state added up to $13.6 billion in leisure and hospitality sales in 2014 and $878 million in state sales tax.
The new study is one way to determine how things have changed in North Dakota since the last one analyzed 2013 spending. Coleman said the latest numbers show some changes, which could be a response to hits to North Dakota's top two industries, oil and agriculture, as well as fewer border crossings because of a weaker Canadian dollar.
While visitor spending grew 8.6 percent in 2014, it fell 9.6 percent in 2015, she said, ending on par with 2013 levels. That's still up about 20 percent, or nearly $500 million, since 2011.
"It's been slow, steady growth," Coleman said of tourism. "Obviously we had some pretty intense years there for a while, but over the long term, it's been a consistent contributor to the economy."
The study said tourism equaled about 4 percent of the state's gross domestic product in 2015 and contributed 5.8 percent to the tax base and $327 million in state and local tax revenues. It also sustained more than 42,000 jobs.
Just under 30 percent of spending was on food and beverages, followed by retail (21.6 percent), gas and local transportation (18.3 percent), lodging (16.3 percent), recreation and entertainment (12.7 percent) and air travel (1.3 percent).
Coleman said the latest figures show tourism is a "stabilizer" that hasn't suffered from the "huge shifts" that have happened with oil and agriculture.
"If they didn't come and pay taxes, and if we didn't pay taxes on those hotels and rental cars or whatever else when we were traveling, then every household would have to pay more in taxes to make that difference up," she said.