Rock County, WI Population

Overview

163,522

Total Population

39.8

Median age

50.42%

Female population %

98.3:100

Gender ratio (M:F)

55-59 years

Largest age group

55.2

Total dependency ratio

White

Largest racial group

15,327

Hispanic population

Sources: U.S. Census Bureau, American Community Survey (ACS) 2021

TABLE OF CONTENTS

Age

Rock County's population is old compared to the rest of the country:

The median age in Rock County is 39.8, compared to 38.8 nationwide, according to the American Community Survey 2017 - 2021 5 Year estimates.
Rock County's population under 18 was 23.21%, compared to the 22.51% nationwide.
Rock County's elderly or the senior population (over 65 age) was 16.54% as compared to 16.04% nationwide.
Of the total population in Rock County, 19.01% were under the age of 15, 18.75% aged 15 to 29, 45.69% aged 30 to 64, 14.66% aged 65 to 84, and 1.89% were 85 years of age and older.

There are 1,378 more females than males in Rock County:

The female percentage in the USA is 50.50% while the male percentage is 49.50%, compared to 50.42% females and 49.58% males in Rock County, WI.
The Rock County, WI gender ratio is 98.3:100 i.e. 98.3 men to 100 women (0.983).
For male population, the largest age group is 60-64 years with a population of 5,828.
For the female population, the largest age group is 55-59 years with a population of 5,956.

Rock County's population has become increasingly diverse:

Racial distribution of Rock County population: 84.47% are White, 4.78% are Black or African American, 0.26% are American Indian and Alaska Native, 1.19% are Asian, 0.02% are Native Hawaiian and other Pacific Islander, 4.14% are some other race and 5.14% are multiracial.
Rock County's racial breakdown clearly shows that there is an absolute majority of White population in the county.
By ethnicity, 15,327 is Hispanic or Latino (of any race), and 148,195 (90.63% of the total population) is Non-Hispanic.
The largest racial group in Rock County is White with a population of 138,122 (84.47% of the total population).

Rock County's population has already reached its peak and is showing a trend of decline:

The peak population was 164,192 in the year 2021
From 2000 to 2010, Rock County's population increased by 7,745 (5.08%), as compared to the national growth of 9.63%.
From 2010 to 2020, Rock County's population increased by 3,490 (2.18%), according to Census Bureau's Population Estimates Program. For the same period, the rate of growth for the United States was 7.17%.
Between the year 2000 and 2022, Rock County's population was lowest in year 2000 at 152,516.