Exploring the demographics of counties in Texas

February 8, 2016

Our most recent open data project is an application to explore the present and future demographics of counties in Texas, using publicly-available data from the Office of the Texas State Demographer.    Please click this link or click the image below to access the application.

The application allows you to interactively explore population pyramids for the 254 counties in Texas from 2010-2050.  Population pyramids are charts commonly used to display the age and sex structure of a population, with male and female populations organized into bars by age group that are reflected around a central vertical axis of zero.  Counties can be selected in the application from the drop-down menu or by clicking a county on the map.  Use the year slider to generate projected pyramids for different years; the projections use the Texas State Demographer’s 0.5 migration scenario, which presumes a net migration rate in the future that is half that of the rate for 2000-2010.  Also, you can choose to display charts for the overall county population, or optionally by racial or ethnic group.  In all, there are 41,656 possible charts that the application can generate, so feel free to explore!  We’ve shared a few that we’ve found interesting below.

County population structure and the life course

The population pyramid of Travis County, which includes the city of Austin, reflects Austin’s popularity as a destination for young professionals and the presence of the University of Texas at Austin.  The largest age cohort for both males and females is 30-34, with proportionately larger numbers in their late 20s and late 30s as well.


Suburban Williamson County to the north of Travis County, however, displays a different structure.


The largest age cohorts in Williamson County span the age ranges of 10-19 and 35-45, with proportionately fewer residents in their 20s and early 30s.  These pyramids suggest a possible relationship between residential location and the life course of individuals; young people growing up in the suburbs and moving to a more urban environment in their 20s, then returning to the suburbs to raise children in their 40s.

The “cultural generation gap”

Demographer William Frey has written of a “cultural generation gap” emerging in the United States between whites and Hispanics/Latinos in many communities, where the population is composed of an aging white population alongside a more youthful Hispanic demographic.  This cultural generation gap is reflected in many counties in Texas, such as Harris County, home to the city of Houston and Texas’s largest county by population.  The white population pyramid for Harris County suggests a disproportionately older population:

Conversely, the population pyramid for Hispanics in Harris County skews much younger:

Animating the two population pyramids through their 2050 projections additionally suggests a white population that is projected to continue to age and decline in overall numbers, in contrast with a Hispanic population that is expected to grow significantly over the next several decades.

Economics and gender imbalance

In many rural counties in Texas, the population pyramids reflect a noticeable gender imbalance.  Sometimes, this has to do with the location of correctional facilities; in other cases, it reflects the economics of the area.  An example of this is La Salle County in south Texas, a key location for oil drilling in the Eagle Ford Shale:


The gender imbalance is notable in the age ranges from 20 to 34; for example, males aged 25-29 outnumber females in that same age bracket 682 to 206.  However, the economics of oil can be volatile in south Texas, as explored in this 2014 article from The New York Times; in turn, future population projections for communities like these are at best uncertain.

There are thousands of other stories that accompany the charts that our application can generate.  Please explore for yourselves, and let us know if you find anything particularly interesting to you!