The US Census Bureau’s recently released county population data shows Atlanta agreeing with the national trend toward a more urban lifestyle. The USA Today recently reported that county population data compiled from 2010 to 2013 shows inner, core counties in metropolitan areas adding more people than outlying counties; a significant shift from most of the 2000’s and much of the past half century. This data, as they conclude, shows that more and more people are choosing urban lifestyles over auto-dependency; while this may be true, county-level data is potentially an inaccurate way of showing it.
Atlanta data may provide an example as to why choosing county-level data is a poor way of showing behavior and lifestyle changes. Many interpreting the US Census Bureau data will ignore the discrepancies between and within counties and base their conclusions on general, non-specific data. Here’s how that is applied to Atlanta: between the years 2010 and 2013, Fulton County added a significantly greater number of people than the large outlying suburbs, even if we include Cobb County as an outlying county. While Fulton added 63,710 residents, Forsyth managed just under 20,000, Cherokee just over 10,000, Cobb just under 30,000, and Clayton just under 5,000. Gwinnett and Dekalb added 54,000 and 21,500, respectively. Clearly this shows that more people preferred to live in urban areas with walkability and less auto-dependence.
Now let’s add in the discrepancies to show why making general conclusions about lifestyles based on county data may be incorrect. Categorizing the Atlanta metropolitan area’s counties as suburban or urban or inner or outer or auto-dependent or walkable is difficult and a bit different than in many other metro areas. No one county can easily be put into a single category. While the majority of the urban core is found in Fulton County, large tracts of land in the county are clearly suburban or rural in nature. The same can be said for Dekalb, though the vast majority of the county does not include what many would consider to be Atlanta’s urban core. Cobb and Gwinnett are essentially suburban, but both, particularly Gwinnett, have large areas that would be classified as denser suburban or even urban.
Simple data shows that to some degree our perception of counties as being either urban, suburban, or rural in terms of density is incorrect. For instance, Clayton County and Fulton County have about the same number of people per square mile (ppsm): roughly 1,870. Cobb not only has more ppsm than Fulton (2,112 to 1,870), but it has twice as many ppsm than Gwinnett (1,369). Perhaps unsurprisingly Dekalb has the most ppsm at 2,671 and Cherokee has the fewest ppsm at 534.
Clearly many of our counties include land that is shaped and used in dramatically different ways. While, overall, Fulton trails both Cobb and Gwinnett in terms of density, the City of Atlanta has 3,330 ppsm (for reference, San Francisco has 17,000 ppsm and Oklahoma City has 990 ppsm). While southeastern Cobb and western Gwinnett are fairly dense, both are smaller than Fulton and also include large swaths of rural areas. Simply looking at county data to conclude how people are living is not accurate, especially when applied to Atlanta. Metro regions contain different configurations of counties and jurisdictions and in some instances comparing county-level data may be an accurate gauge of lifestyle. However, with metro regions having so much variation, national trends shouldn’t be compiled from such data.
The strange configuration of Atlanta counties makes it difficult to compare our county data within the metro area to county data within other metro areas. For instance, the entire city of Houston and much of its suburbs lie solely within Harris County. The entire city of Phoenix and its suburbs lie solely within Maricopa County. The entire Miami metro area lies within Miami-Dade and Broward Counties. The entire Seattle metro area lies within King, Snohomish, and Pierce Counties, with the vast majority being in King.
On the opposite side of the spectrum are those metro areas made up of many smaller counties. While the rest of DC is similar to Atlanta in that it is made up of counties that cannot be easily classified, the DC metro area contains counties that are wholly occupied by the urban core, unlike the previously mentioned counties that contain entire metro areas. DC’s urban core is the District (counted as a county by the Census) and Arlington County. Boston and New York also have small counties that are entirely filled by urban, dense land uses.
Due to the dramatic differences in the size and density of counties nationwide, it isn’t wise to just look at county-level data to decide changing lifestyle choices nationally. Dense, suburban, and rural land uses exist in Maricopa and Fulton Counties, but generally only dense land uses exist in Arlington and Suffolk (MA, Boston) Counties. Many studies or reports will classify every county in a metro region as either inner or outer. though the four counties just mentioned have varied land uses, all will likely be deemed “inner, core counties.”
The USA Today article shows more people living in inner, core counties than outlying counties and concludes that because of this, more people are choosing a certain urban lifestyle. This classification scheme is clearly problematic because Maricopa or Fulton Counties, though they will be classified as “inner, core counties,” contain many different land uses, so it is impossible to discern the lifestyle of the counties’ new residents. Suffolk will also be classified as “core,” though the county only contains dense land uses so the lifestyle of new residents is fairly predictable. Though in realty more people may be choosing to live car-free, walkable lifestyles, county-level data isn’t the best way to present this idea in a national, and in most circumstances, a local framework.
Ultimately we can look at census tract data instead of county-level data to get a much closer look at exactly where people are moving within a county. This requires much more work because it involves analyzing thousands of different tracts within counties to track population changes over time. It is much easier to track changes in tens or hundreds of counties and just rely on generalized data. Clearly more people are choosing to live closer to cities rather than farther from cities. Whether this means they are adopting certain urban lifestyles is something than can generally be inferred from county-level data, but cannot be fully understood until we get a look at data on a much more localized scale.
The US Census is scheduled to release the latest population data for cities in May.