So far, more people are visiting Yellowstone National Park this year compared to this time last year.

Visitation at the park is up 14.65 percent for the first five months of the year compared to the same time period in 2015. This May saw 15 percent more visitors than last May.

Park managers believe the National Park Service’s Centennial year, marketing and tourism promotions by Montana and Wyoming, and lower gas prices could have something to do with the record number of visits to the park so far this year.

All five park entrances saw more vehicles this May compared to May 2015. The West Entrance recorded the largest increase in May, with 9,175 more vehicles than May 2015. The most striking increase in vehicle traffic this month was with buses, according to the park. There were 48 percent more buses (594 vehicles) this May compared with May 2015.