After his son graduated from Doland's high school, Hubert Humphrey, Sr. left Doland and opened a new drugstore in the larger town of Huron, South Dakota; a population of 11,000 people, where he hoped to improve his fortunes. Because of the family's financial struggles, Humphrey had to leave the University of Minnesota after just one year. He earned a pharmacist's license from the Capitol College of Pharmacy in Denver, Colorado (completing a two-year licensure program in just six months), and spent years from 1931 to 1937 helping his father run the family drugstore. Over time the Humphrey Drug Company became a financial gain business and the family again succeeded.