2020 census

As of the 2020 census, Dover had a population of 13,112. The median age was 42.0 years. 22.1% of residents were under the age of 18 and 23.1% of residents were 65 years of age or older. For every 100 females there were 94.4 males, and for every 100 females age 18 and over there were 90.3 males age 18 and over.^[14][15]

99.8% of residents lived in urban areas, while 0.2% lived in rural areas.^[16]

There were 5,366 households in Dover, of which 27.5% had children under the age of 18 living in them. Of all households, 46.7% were married-couple households, 17.6% were households with a male householder and no spouse or partner present, and 29.0% were households with a female householder and no spouse or partner present. About 32.6% of all households were made up of individuals and 17.5% had someone living alone who was 65 years of age or older.^[14]

There were 5,766 housing units, of which 6.9% were vacant. The homeowner vacancy rate was 0.9% and the rental vacancy rate was 8.5%.^[14]

2010 census

As of the census^[17] of 2010, there were 12,826 people, 5,181 households, and 3,297 families living in the city. The population density was 2,254.1 inhabitants per square mile (870.3/km²). There were 5,578 housing units at an average density of 980.3 per square mile (378.5/km²). The racial makeup of the city was 94.1% White, 1.1% African American, 0.6% Native American, 0.5% Asian, 0.7% Pacific Islander, 1.7% from other races, and 1.4% from two or more races. Hispanic or Latino of any race were 4.1% of the population.

There were 5,181 households, of which 28.5% had children under the age of 18 living with them, 49.7% were married couples living together, 9.8% had a female householder with no husband present, 4.1% had a male householder with no wife present, and 36.4% were non-families. 31.6% of all households were made up of individuals, and 15.6% had someone living alone who was 65 years of age or older. The average household size was 2.37 and the average family size was 2.96.

The median age in the city was 42.9 years. 22.3% of residents were under the age of 18; 7.3% were between the ages of 18 and 24; 22.9% were from 25 to 44; 25.6% were from 45 to 64; and 22% were 65 years of age or older. The gender makeup of the city was 47.4% male and 52.6% female.

2000 census

As of the census^[4] of 2000, there were 12,210 people, 4,996 households, and 3,362 families living in the city. The population density was 2,319.6 inhabitants per square mile (895.6/km²). There were 5,233 housing units at an average density of 994.2 per square mile (383.9/km²). The racial makeup of the city was 97.09% White, 1.27% African American, 0.25% Native American, 0.51% Asian, 0.02% Pacific Islander, 0.20% from other races, and 0.66% from two or more races. Hispanic or Latino of any race were 0.60% of the population.

There were 4,996 households, out of which 30.2% had children under the age of 18 living with them, 54.4% were married couples living together, 10.0% had a female householder with no husband present, and 32.7% were non-families. 28.8% of all households were made up of individuals, and 14.9% had someone living alone who was 65 years of age or older. The average household size was 2.39 and the average family size was 2.94.

In the city, the population was spread out, with 24.1% under the age of 18, 6.7% from 18 to 24, 26.8% from 25 to 44, 22.5% from 45 to 64, and 19.9% who were 65 years of age or older. The median age was 40 years. For every 100 females, there were 86.9 males. For every 100 females age 18 and over, there were 83.1 males.

The median income for a household in the city was $36,665, and the median income for a family was $44,604. Males had a median income of $34,579 versus $22,397 for females. The per capita income for the city was $18,928. About 7.5% of families and 9.2% of the population were below the poverty line, including 11.1% of those under age 18 and 9.7% of those age 65 or over.