The Transportation Lifestyles of Single People, Part 2 — Trends: What the Data Says
The transportation choices of Americans who live alone are important not just because singles make up over one quarter of all households. Between 2010 and 2015, the 32 million one-person households in the United States became both more likely to live car-free and to have multiple cars. (Yes, a one-person household with two-or-more cars is a thing!) The transportation lifestyles of singles are shifting, even volatile. Moreover, their choices are an indicator that transportation lifestyles are polarizing across the states, and also across some of the largest metros and their core cities too.
Recap of The Transportation Lifestyles of Single People, Part 1: People living alone are twice as likely as households overall to live car-free, and they make up 57 percent of all car-free households in the United States. Although the majority of singles, 66 percent, have only one vehicle, 15 percent of singles have multiple cars. In transportation lifestyle terms, this latter group lives car-two+. In only 20 states and 27 of the 50 largest metros do singles living car-free outnumber singles living car-two+. Transportation observers are right to celebrate singles and car-free living, but they should also pay attention to people who live alone yet still have multiple vehicles.
Transportation lifestyles are simply how people connect to the world and get things done. As explored in Part 1, car-free lifestyles can be attractive to people who live alone. They are more likely to have enough flexibility to be able to build their lives around other modes of travel. They are also particularly vulnerable to transportation failure. In some places, however, this same need for transportation resilience can lead singles to have multiple cars. Part 2 uses changes in car ownership (or vehicle availability) between 2010 and 2015 as a proxy for trends in transportation lifestyles.
All data for Part 2 is drawn from American Community Survey (ACS) Table B08201, Household Size by Vehicles Available. The analysis uses the five-year estimates for 2006–2010 and 2011–2015 and focuses on relatively large shifts — increases or decreases of at least 0.5 percentage points between 2010 and 2015 — in the proportion of singles living car-free and car-two+. “Have a car” means to have a car, van, or small truck available at home for personal use. “Singles” is short hand for one-person households or people who live alone.
Rankings of shifts in transportation lifestyles for states, the 50 largest metros by population, and their core cities can be found in Tables 5–10.
An example from the city of Los Angeles illustrates what I mean by shifts in transportation lifestyles. In 2010, among one-person households in Los Angeles, 20.7 percent had no car, 68.3 percent had only one car, and 10.9 percent had multiple cars. In 2015, among one-person households, 22.7 percent had no car, 67.8 percent had only one car, and 9.5 percent had multiple cars. Singles in Los Angeles shifted away from cars, as living car-free became more common (or went up) by 2.0 percentage points and living car-two+ became less common (or went down) by 1.4 percentage points.
Polarization in the States
For the states, singles in Nevada made the largest shift to car-free living, an increase of 1.8 percentage points between 2010 and 2015. Singles in Alaska made the largest shift to having multiple cars; living car-two+ went up by 3.6 percentage points.
Led by Nevada and Alaska, trends among the states showed a pronounced polarization underway between 2010 and 2015. Singles in 15 states shifted away from cars, but in 13 states they shifted towards having more cars. Three states polarized within themselves: singles in Indiana, New Mexico, and Nebraska became more likely to live both car-free and car-two+.
The shifts within states tended to the extremes. Singles in 2015 were more likely to live car-free or car-two+, rather than to have added/dropped a vehicle in order to have (only) one car. Singles made car-free living more common in 12 of the 15 states showing shifts away from cars. Singles in 11 of the 13 states shifting towards having more cars made living car-two+ more common. New Hampshire is the only state where the two extremes converged on having only one car.
Three states — California, Idaho, and Rhode Island — showed a strong shift away from cars: singles became less likely to live car-two+ and more likely to live car-free. Five states — Alaska, Arkansas, Pennsylvania, South Dakota, and West Virginia — experienced a strong shift towards having more cars. Living car-free in these five states became less common, while living car-two+ became more common.
Polarization continued when looking at the largest shifts. Car-free living became more common by greater than one percentage point in five states: Nevada, Michigan, Indiana, Washington, and Rhode Island. Singles with two-or-more cars, however, became more common by over one percentage point in seven states, and in Texas, ranked eighth, singles shifted to living car-two+ by just under one percentage point.
State-level polarization was mostly regional: singles in the western states moved away from cars, while those in the Great Plains states added cars. Eastern states had less dramatic changes in transportation lifestyles, but singles in states with shifts tended to let go of cars. Pennsylvania is a notable outlier. Despite the state’s pre-automobile urban fabric and large legacy transit systems, its singles added cars at about the same pace as singles in Texas.
Metropolitan Areas Lean Car-Free
Singles let go of cars in half of the 50 largest metropolitan areas by population between 2010 and 2015. Singles in 15 metros shifted to car-free living by over 1.0 percentage point and by over 2.0 percentage points in the metros encompassing Indianapolis, Las Vegas, and San Francisco. In just 11 metros were singles more likely to have more cars in 2015.
Like for the states, shifts tended to be towards the extreme transportation lifestyles. In the 25 metros where singles shifted away from cars, 22 metros showed increases in car-free living. Only in the metros encompassing Louisville, San Diego, and Atlanta were the shifts predominantly about dropping down to only one vehicle. Singles made living car-two+ more common in seven of the 11 metros with more cars. Only in the metros encompassing New York, Boston, Raleigh, and Cincinnati was the predominant shift a move from no car to one car.
Eleven metros experienced strong shifts away from cars, where living car-free went up and car-two+ went down. The eleven are the metros encompassing Hartford, Detroit, Milwaukee, Providence, Washington, Salt Lake City, Portland, San Francisco, Sacramento, Los Angeles, and Riverside. Six metros polarized between 2010 and 2015: proportionally, more singles were living both car-free and car-two+ in the metros encompassing Indianapolis, New Orleans, Oklahoma City, Memphis, Dallas, and Charlotte.
Strong shifts towards more cars (car-two+ up and car-free down) only showed up in the metros encompassing San Antonio, Pittsburgh, and San Juan. Only in the metros encompassing Memphis, New Orleans, and Dallas did singles embrace living car-two+ by over one percentage point.
Singles in Core Cities Also Let Go of Cars, With Exceptions
Singles in the core cities of the 50 largest metropolitan areas created a lot of volatility in transportation lifestyles between 2010 and 2015. Only seven cities did not meet the +/-0.5 percentage point threshold for change.
Similar to metros, most of the lifestyle shifts for singles were away from cars. Sixteen cities experienced strong shifts: car-free living went up and car-two+ went down. The remaining eight cities split evenly: in Indianapolis, Baltimore, Chicago and Phoenix only car-free living became more common and in Louisville, Riverside, San Diego, and Minneapolis singles only shifted from multiple cars to one car.
Car-free living attracted some very large shifts. It became more common by over one percentage point in 20 cities and by over two percentage points in nine. Of these latter nine cities, however, the total number of households increased only in San Francisco, Indianapolis, Seattle, and Washington. Increases in the proportion of singles living car-free is likely to mean something very different in shrinking cities like Detroit and Cleveland than in fast-growing cities like Seattle and Washington.
Five cities — Las Vegas, New Orleans, Memphis, Dallas, and Oklahoma City — experienced polarization: both living car-free and living car-two+ became more popular. Atlanta is the only city where singles converged on having (only) one car.
Singles added cars in 13 core cities, but in only two of these cities, Richmond and Orlando, did singles exhibit strong shifts, both away from living car-free and towards living car-two+. Unlike for singles in states and metros, the predominant shift when singles in cities added cars was not to the car-two+ extreme but from no vehicle to one vehicle.
Did Singles in Cities Lead Metros Away from Cars? Sometimes.
The urban heart of metros would seem to be the most likely place for singles to adopt new transportation lifestyles with fewer cars. For many metros, shifts were as expected: the moves singles made away from cars were larger in the core cities than in the metros as a whole. Seattle and Charlotte are examples of the expected metro/core city pattern. For Seattle, the shifts to car-free living and away from multiple vehicles were much larger in the core city than its metro as a whole. Charlotte’s metro as a whole became more polarized — both living car-free and car-two+ went up — but singles in the core city only let go of cars.
However, 23 core cities deviated in some way from this expected pattern. In these 23 cities, singles in the metros as a whole let go of cars at a higher rate than singles in the core cities, or, in regions where singles added cars, singles in the core cities outpaced those in the metros in adding cars.
In the 28 metros where car-free living went up, the pattern in 20 metros is as expected. Eight metros, however, beat out their core cities. Although car-free living did become more common in the cities of Las Vegas, St. Louis, New Orleans, and Hartford, their respective metros experienced even larger shifts to living car-free. A similar pattern holds for the metros encompassing Kansas City, Minneapolis, Riverside, and Portland: car-free living became more common for singles in the metros as a whole, but not for singles in their core cities.
Orlando showed the largest, unexpected divergence between metro and core city: car-free living became more common in the metro as a whole, but for singles in the core city car-free living went down while car-two+ went up. Eight additional core cities led their metros away from car-free living, including the cities of Philadelphia, Columbus, Atlanta, Nashville, Denver, Richmond, Cincinnati, and Pittsburgh.
For metros where the proportion of singles living car-two+ went down, the expectation is that shifts away from multiple cars would be larger in the core cities than in the regions as a whole. This was indeed the case for 11 of the 14 metros, but in the metros encompassing San Francisco, Portland, and Providence shifts away from living car-two+ were equal to or larger in the metros as a whole than in their core cities.
For metros where the proportion of singles living car-two+ went up, the expectation is that living car-two+ would be embraced more in the metros as a whole than in their core cities. This pattern held for nine of these 13 metros but not for the metros encompassing New Orleans, Nashville, Austin, or Oklahoma City. In these four metros, the shifts to living car-two+ were larger in the core cities than in their metros as a whole. In addition, more singles have been attracted to living car-two+ in the core cities of Boston, Richmond, Las Vegas, Orlando, and Miami, although living car-two+ in their respective metros did not change.
Singles in these 23 metropolises are reminding transportation observers to always question their assumptions. American metropolitan areas are very diverse, complex places. Minneapolis is the core city because it is the larger twin of the Twin Cities. Las Vegas has dense development that for historical reasons is outside the city limits. The core cities in many metros are surrounded by inner ring suburbs built before 1930. In addition, many southern and western cities have large areas of recently developed land that is indistinguishable from suburbs. Many of America’s core cities are also getting wealthier: that the singles living in them — professionals, empty nesters, or retirees — add or bring in cars shouldn’t be that much of a surprise.
People live alone in cities, suburbs, and rural areas, and these singles are young adults, the middle aged, and the elderly. Their transportation lifestyle choices between 2010 and 2015 (really 2006 and 2015) are a reality check on the popular narratives about Americans and their changing relationships to automobiles. Their choices confirm that, yes, something is definitely afoot: 32 states, 42 of the 50 largest metros, and 43 of their core cities had shifts around living car-free or car-two+ that met the +/- 0.5 percentage point analysis threshold. In addition, singles in 15 states, 19 metros, and 33 core cites produced lifestyle shifts larger than +/- 1.0 percentage points.
The polarization is striking: singles, by and large, shifted to the extremes — to car-free or multiple cars — instead of converging on only one car. West of the Rocky Mountains, singles in metropolitan areas led their states away from cars. Singles in many northern cities did the same, although often without the growth dynamics of the west. East of the Rocky Mountains and south of a line running from Denver east to Pittsburgh and Philadelphia, singles added a lot of cars, but some enclaves that support car-free living strengthened. Part 3 examines whether polarization also describes trends in transportation lifestyles for American families.
This essay is part of a larger project that uses transportation lifestyles to improve transportation planning and land development. For more information, contact me at sjpeterson [at] 23urbanstrategies [dot] com.