2020 census As of the
2020 census, Buena Vista County had a population of 20,823 and a population density of . 89.44% of the population reported being of one race. There were 8,141 housing units, of which 7,447 were occupied. The median age was 35.7 years. 26.4% of residents were under the age of 18 and 16.2% of residents were 65 years of age or older. For every 100 females there were 102.2 males, and for every 100 females age 18 and over there were 100.8 males. The racial makeup of the county was 60.5%
White, 2.8%
Black or African American, 0.6%
American Indian and Alaska Native, 9.2%
Asian, 3.0%
Native Hawaiian and
Pacific Islander, 13.4% from some other race, and 10.6% from
two or more races.
Hispanic or Latino residents of any race comprised 28.5% of the population. for Buena Vista County from
ACS 5-year estimates
2010 census The 2010 census recorded a population of 20,260 in the county, with a population density of . There were 8,237 housing units, of which 7,522 were occupied.
2000 census As of the
census of 2000, there were 20,411 people, 7,499 households, and 5,121 families residing in the county. The
population density was . There were 8,145 housing units at an average density of . The racial makeup of the county was 88.00%
White, 0.35%
Black or
African American, 0.13%
Native American, 4.33%
Asian, 0.01%
Pacific Islander, 5.75% from
other races, and 1.42% from two or more races. 12.54% of the population were
Hispanic or
Latino of any race. 2005 Census estimates of the racial origins of Buena Vista County's population indicated it had the lowest percentage of non-Hispanic Whites of any county in Iowa. The non-Hispanic whites constituted 76.1% of the county's population, with African-Americans being 1.3%, Asians 3.9% and Latinos 18.6% of the population. There were 7,499 households, out of which 31.90% had children under the age of 18 living with them, 57.50% were
married couples living together, 7.20% had a female householder with no husband present, and 31.70% were non-families. 27.00% of all households were made up of individuals, and 13.20% had someone living alone who was 65 years of age or older. The average household size was 2.54 and the average family size was 3.08. In the county, the population was spread out, with 25.40% under the age of 18, 12.20% from 18 to 24, 25.40% from 25 to 44, 20.20% from 45 to 64, and 16.90% who were 65 years of age or older. The median age was 36 years. For every 100 females there were 100.40 males. For every 100 females age 18 and over, there were 97.40 males. The median income for a household in the county was $35,300, and the median income for a family was $41,549. Males had a median income of $29,172 versus $20,252 for females. The
per capita income for the county was $16,042. About 7.60% of families and 10.50% of the population were below the
poverty line, including 12.60% of those under age 18 and 7.60% of those age 65 or over. ==Law enforcement==