Last night a post by local blogger Wordbones caught my eye. Based on a story in the Baltimore Sun, it discussed proposed plans for affordable housing in Columbia Town Center, housing that would be reserved for those with income of less than $80,000 (10% of total units) or those with income between $80,000 and $120,000 (another 10% of total units). Wordbones particularly noted a quote in the article from Alan Klein of the Coalition for Columbia’s Downtown:
Klein noted that 80 percent of the 5,500 residential units planned would be for people making more than $120,000, which he defined as the wealthy few. It seems like a pretty elite group, said Klein, referring to the 20 percent [of units reserved for those making less than $120,000] as a drop in the bucket.
Wordbones questioned this characterization, and I myself was curious as to whether it was really true. When in doubt the best rule is to go to the data, which in this case are from the annual American Community Survey  produced by the US Census Bureau. In some comments on Wordbones’s blog I referenced the 2006 ACS data, but as it turns out the 2007 ACS estimates were just released, as highlighted in a recent Columbia Flier story about Howard County being the third-wealthiest county in the country.
So what do the data say? According to the detailed breakdown of household income for Howard County in 2007, about 37% of Howard County households have incomes of $125,000 or more ; if we add in the households between $120,000 and $125,000, and also allow for the effects of wage inflation over the past year, almost 40% of Howard County households (or nearly two out of five) are part of Alan Klein’s pretty elite group.
But wait, there’s more! The ACS distinguishes households from families ; among other things, the ACS definition of family excludes people living alone. If we look at the detailed data for Howard County family income for 2007 we find that 46% of Howard County families have family incomes of $125,000 or more. Also, the median Howard County family income for 2007 was $115,907, meaning 50% of Howard County families had income higher than that. So if we again add in the effects of wage inflation it’s likely that Alan Klein’s weathy few (for whom 80% of the proposed units are
reserved intended) includes half the families in Howard County.
To give Klein his due, $120,000 is an unusually high income for the US as a whole; detailed household income data for the entire US show that only 12% of US households had income of $125,000 or more in 2007, and the corresponding data for family income show that less than 16% of US families had family income above that level. This underscores the unusual position of Howard County as a very wealthy jurisdiction. Wordbones doubted whether any typical family in Columbia with a household income of $120,000 sees themselves as being wealthy, and in the context of Howard County at least he’s absolutely right.
The ACS is a survey based on random samples, not a comprehensive survey like the ten-year census. Because of that there is some sampling error in the results, such that the true figures might be a few percentage points higher or lower. I’ve ignored this in my discussion (as do most press stories on the ACS data).
ACS figures are in 2007 inflation-adjusted dollars. I wondered a bit about what this meant until I figured it out: ACS data are taken throughout the year, and wage inflation over the course of the year causes incomes to increase slowly from month to month. The Census Bureau uses monthly inflation figures to adjust the numbers so that they are comparable, i.e., as if they were all taken in a single month in 2007.
According to the official ACS definitions, [a] household includes all the people who occupy a housing unit, while [a] family consists of a householder and one or more other people living in the same household who are related to the householder by birth, marriage, or adoption. In general the number of families will be less than the number of households: Not all households contain families since a household may be comprised of a group of unrelated people or of one person living alone — these are called nonfamily households. Thus, for example, in the 2007 ACS data Howard County is estimated as having 98,866 households but only 73,765 families.