Thursday, June 26, 2014

Visualizing Sprawl

Some big US cities are dense, while others are spread out. This affects the economy, quality of life, and the environment. Here's a way to visualize the residential density of the country's 12 largest regions and their varying levels of sprawl.

Residential density of census tracts in and around the District of Columbia and Baltimore
(magnified 200% in each direction, relative to visualizations below)

Earlier this year, Smart Growth America released a report titled Measuring Sprawl 2014, finding that New York is the country's "most compact, connected large metro area," with an index score of 203.4, while Atlanta is the "most sprawling," with a score of 41.0.

But what does that gap really look like? The world's most iconic skyline on one extreme, contrasted with a highway full of motorists stranded overnight due to a snowstorm on the other? What about viewed through a wider angle lens, at a regional level? Next City recently published a series of GIFs illustrating regional sprawl over time, and this post tells a similar story from a different perspective.

The visualizations below show residential density (as one unit of height for every person per square mile), by census tract, for the nation's 12 statistical areas of at least 5 million inhabitants. The images show Combined Statistical Areas (CSAs) with the exception of Miami, which until recently was not part of a CSA. The regions are viewed from the same height and distance, but from different directions, most often from the south.

Note: One census tract, 307.2 in Chicago, was omitted from this visualization as its population density is off the charts. The tract essentially encompasses only the land on which these three high rises are located.

Cross-posted on Greater Greater Washington

Friday, April 4, 2014

Where Are DC's Corner Stores?

Originally Printed/Posted in the Washington City Paper on February 26, 2014

Displaying Corner Store GraphicV3.jpg

Sure, you know the place down the block from you, and maybe the one a couple of streets over. And the one by your friend’s house where you sometimes stop by to pick up a six-pack on your way to visit. But how many corner stores are there in the District, all told?

Defining them is more art than science, but here’s a stab at systematically identifying all of D.C.’s businesses that fit the bill. Each of these establishments has an active retail license to sell alcohol, cigarettes, groceries, and/or food products, in a building and property of less than 10,000 square feet, located within 150 feet of a zone that allows residential development. Chain grocery stores and pharmacies don’t count, nor do gas stations.

That adds up to more than 500 stores. Quite a few of their names give deference to “The Corner” (Charlie’s Corner, Cookie’s Corner, Cornercopia) or to the intersecting streets that form the corner (18th & D Liquors) or both (11-M Corner Market). Many are joint ventures: P&C, B&M, K&H (and just about every other possible permutation), Stop & Go, Me & My, Night N Day.

This map shows where these corner stores are located and identifies some of the neighborhoods blessed with the highest concentrations of such establishments. The densest stretch? A strip near Kennedy Street and Georgia Avenue NW, with one store for every 170 residents of the surrounding blocks.

Monday, January 6, 2014

A Visual Representation of Consumer Expenditures by Household Income

Data from the Bureau for Labor Statistics show that people of all income levels tend to spend similar percentages of their budgets on each expenditure category, with some exceptions. For example, as income rises, Consumer Units (defined as families living together, financially independent individuals, or groups of unrelated individuals who budget jointly) dedicate an increasing percentage of their budget to personal insurance and pensions. Consumers at the lower end of the income spectrum spend a disproportionately higher percentage of their budget on housing costs. But on most other measures, including transportation, health care, and entertainment, the percentages across income levels are fairly equivalent, as shown in the graph below:

But these percentages represent share of total expenditures, and not all Consumer Units are operating with a balanced budget. A comparison of income and expenditures shows that lower income families and individuals tend to spend more than they earn while higher income units are able to stash some of their earnings away. The graphs below attempt to illustrate this:

When you change the denominator in the first graph from Total Expenditures to Annual Income, a more accurate depiction of our spending habits is revealed. Consumers earning between $5,000 and $30,000 per year spend 62% of their income on Housing, 24% on Transportation and 23% on Food. That's 109% of their income gone just on these three basic necessities.

This modified version of the first graphic presented gives a fuller representation of household finances at different income levels in the US and paints a pretty bleak picture for low income families and individuals.



An important question came up in response to the post above: Do the income figures include government assistance programs? The answer is mostly yes.

The chart above shows the percentage of total income by source for consumer units at different income levels. Income includes benefits from programs such as Social Security, the Supplemental Nutrition Assistance Program, and Unemployment Insurance. It excludes benefits that are paid directly to a service provider, such as Medicaid or Housing Choice Vouchers, but those amounts are also excluded on the expenditures.

 The major source of income that is not accounted for here, or in yesterday's graphs, is refundable income tax credits. That mechanism helps close the gap between after tax income and expenditures slightly for lower income households, but there is still, on average, a significant shortfall that must come from a nongovernmental source.

Thursday, January 2, 2014

Anacostia and Its Surroundings: 1892 to Present

If you haven't seen the 1892 Map of Rural Anacostia that Ghosts of DC posted earlier this week, you should check it out.

What first struck me about the map when I saw it was how close the banks of the Anacostia River were to the neighborhood. My knowledge of DC history is minimal, so I did not know that between 1882 and 1927 the tidal marshes along the edge of the Anacostia were filled in, creating what would today appear on a map as Poplar Point.

The graphic below illustrates some of the other physical changes the neighborhood and its surroundings have undergone in the last 120 years. Clusters of single family homes were developed and remain intact in places such as north of today's Good Hope Road (in the Fairlawn neighborhood) and around Morris Road. In the next ring of development, south and east of here, small apartment buildings become the predominant land use. And over time (as early as 1900 with the development of the Nichols School, which is now the Thurgood Marshall Academy), larger footprint buildings sprouted up on and around today's Martin Luther King Jr. Avenue and Good Hope Road.

Future development plans suggest that the next phase of growth will follow a similar trajectory, with moderate densification of the main commercial corridors and substantial expansion into previously undeveloped land, in this case Poplar Point.

Cross-posted on Greater Greater Washington