OMAHA, Neb. (AP) — A monthly survey report suggests that business conditions improved last month in nine Midwest and Plains states.The report issued Wednesday says the Mid-America Business Conditions Index rose to 55.2 in December from 54.1 in November. The October reading was 54.9.Creighton University economist Ernie Goss oversees the survey, and he says the shortages of skilled workers are still holding back even stronger growth.The survey results are compiled into a collection of indexes ranging from zero to 100. Survey organizers say any score above 50 suggests growth. A score below that suggests decline.The survey covers Arkansas, Iowa, Kansas, Minnesota, Missouri, Nebraska, North Dakota, Oklahoma and South Dakota.