CTA car

Photo: Alex Garcia/Chicago Tribune

One of my friends, @muziejus, was so taken with the New Yorker's map of the New York subway by median income that he made his own. It's not quite as fancy looking, but it's still really interesting.


He also did some analysis of it:

In short, the graphs affirm most of what we already knew. Though I also was not expecting the Blue Line to be so much nicer between Western and Grand than it is in the Loop.

There’s also at least one startling hiccup: the huge dive in median income at the Sedgwick stop on the Brown and Purple Lines. I double checked everything, and that’s the correct tract number. I can only guess that there’s a residual effect of Cabrini-Green’s ghost that’s pulling that number down.

It's true: the second-highest median income by El stop is Western on the Blue Line ($106,759, statistically insignficant from Linden on the Purple Line at $106,765). This surprised us—it's much higher than Damen*. But I think I get it. Here's the specific census tract that includes the Western stop:

The Western stop is just barely in the census tract around Ehrler Park. And that's a pricey area. Just browsing around on Zillow, it contains lots of expensive, post-crash single-family home sales: $622,500 in March; $855,000 in August 2010; $1.035 million in May 2012; and so forth. More than half the households in that tract (NB: the margin of error is significant, so take it with a grain of salt) make more than $100k.

But if the Western stop was included in the census tract immediately to the west—which it's partially in—the median income would fall to $66,087. Only 33 percent of households make more than $100,000.

As to the Sedgwick stop near Old Town (median income $14k, mean income $61k), it is where Cabrini-Green used to be. But he's using 5-year American Community Survey estimates, which take a rolling sample from 2007-2011. Parts of Cabrini-Green still existed in 2007. According to the ACS data, over 1,000 families make less than $15k; a little less than 500 make more than $100k.

In the tract immediately to the east, the median is $91k and the mean is $138k. There, almost 500 households make more than $200k. The ACS happened to catch the tract around Sedgwick during a period of profound change.

* The median income around the Damen stop is about $100k. But the two tracts on the other side of North Avenue from the Damen stop have median incomes of $167,240 (with a mean of almost $250k) and $141k. Which is worth keeping in mind: the data (including the New Yorker​'s data) covers the census tract the stop is in, not necessarily what you'd consider to be "around" the stop.