 Among Duluth's households, 26.6% had children under 18, 41.4% were married couples living together, 11.4% had a female householder with no husband present, and 43.9% were non-families.34.5% of all households were one-person households, and 13.3% had someone 65 or older living alone.The average household size was 2.26 and the average family size was 2.90.