OMAHA, Neb. (AP) — A survey of bankers in 10 Midwest and Great Plains states reflects continued economic growth in the region, which boasts strong agricultural performance and rising commodity prices.The Rural Mainstreet Index rose to 59.7 in December, the highest survey figure since June 2007. The index hit 58.4 in November, 52.9 in October and 52.2 in September. Survey organizers say that whenever the index, which ranges from 1 to 100, is above 50, it suggests the economy will grow.Creighton University economist Ernie Goss, who oversees the survey, says growth in U.S. regions tied to agriculture and energy are outpacing urban areas.The survey covers Colorado, Illinois, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, South Dakota and Wyoming.