Racial and ethnic composition 2020 census As of the
2020 census, Plaquemine had a population of 6,269. The median age was 40.4 years. 23.5% of residents were under the age of 18 and 20.0% of residents were 65 years of age or older. For every 100 females there were 91.0 males, and for every 100 females age 18 and over there were 88.2 males age 18 and over. 100.0% of residents lived in urban areas, while 0.0% lived in rural areas. There were 2,596 households in Plaquemine, of which 29.3% had children under the age of 18 living in them. Of all households, 34.7% were married-couple households, 21.0% were households with a male householder and no spouse or partner present, and 37.4% were households with a female householder and no spouse or partner present. About 32.0% of all households were made up of individuals and 14.7% had someone living alone who was 65 years of age or older.
Income and poverty From 2015 to 2019, the median household income was $44,457, and the per capita income was $24,871. Approximately 27.0% of the population lived at or below the poverty line.
2000 census At the
2000 United States census, there were 7,064 people, 2,593 households, and 1,846 families residing in the city. In 2000, 29.7% of households had children under the age of 18 living with them, 44.0% were married couples living together, 22.7% had a female householder with no husband present, and 28.8% were non-families. About 26.5% of all households were made up of individuals, and 10.5% had someone living alone who was 65 years of age or older. The average household size was 2.64 and the average family size was 3.21. In 2000, the median income for a household in the city was $28,364, and the median income for a family was $32,971. Males had a median income of $34,868 versus $21,016 for females. The per capita income for the city was $14,066. About 23.6% of families and 24.4% of the population were below the poverty line, including 35.8% of those under age 18 and 17.5% of those age 65 or over. ==Culture==