Later this month the new 9.7 km North-South metro line in Amsterdam will start service. Like most large scale infrastructure projects, its opening has been delayed many times. 8 times according to this source. But this post is not about that. It’s about a byproduct of the line’s construction. 

The excavations required for the line meant that two sections of the Amstel River – namely the Damrak and Rokin sites – had to be drained. This took place from 2003 to 2012 and gave archaeologists unprecedented access to the bottom of a river in the middle of a historic city center.

Amsterdam started as a small trading port along the banks of the Amstel River some 800 years ago. So not surprisingly, they found a few things. Over 17,000 objects were found and all of them have been catalogued online according to time period, use, material, and location found.

For the full catalogue of objects, click here. Screenshot of the catalogue shown above. And to learn more about the entire project, start here. There’s a lot of good stuff in there for city nerds.

Urbanist Richard Florida has spoken a lot about a “great inversion.” This is about poverty moving to the suburbs and the core of cities becoming a kind of “gated suburb.” (i.e. wealthy)

In response to this narrative, City Observatory recently published a post where they call this a new mythology. Joe Cortright argues that it is simply an exaggeration that sounds good in media headlines. And indeed, if you look at some accounts of poverty, the swings haven’t been that dramatic.

However, if you dig into this study by Luke Juday at the University of Virginia (cited in the City Observatory article), there have been some interesting changes. 

Below is a chart that shows the percentage of adults (over 25) with a bachelor’s degree (or higher) sorted by distance from the city center. This particular chart is a composite of 7 northeastern (US) cities. The brown line is 2012 and the orange line is 1990.

As you can see, there has been a huge spike in educated people living in city centers – at least in the northeast.

Here is that same chart for Atlanta:

New York:

In the case of New York, it looks like the entire city just became more educated.

Miami:

Educational attainment is often the single biggest determinant of income. So there is something to be said about highly educated people concentrating themselves in city centers. We may not want to call it an inversion of great proportions, but it’s a meaningful shift.

Jeffrey Lin, who is an economist at the Federal Reserve Bank of Philadelphia, recently published the following chart:

I found it in this Washington Post article. And it’s packed full of fascinating information.

The chart compares the socioeconomic status in US cities (y-axis) against “distance from city center” (x-axis) in 1880 and then in recent years (1960 to 2010 census data). The orange circles represent the 1880 data and the red and blue lines represent the recent census data.

What this chart and research tells us is that in 1880, rich people overwhelmingly lived in the center of cities. And as you moved further away from the city center, socioeconomic status fell off pretty precipitously. This makes sense given that, at the time, it was hard to get around and travel long distances.

However, in the post-war years, the exact opposite became true. We began driving and wealth decentralized. This should surprise no one. 

But what’s interesting is how this appears to be reversing. In 2010 (the red line), there’s a sharp increase in socioeconomic status for people living basically right in the center of cities. And for the 30 - 60 km range, there has been a decrease in socioeconomic status essentially from the 1960s onwards. 

The important takeaway here – which is spelled out in the Washington Post article – is that the neighborhoods which appear to be in high demand today are also in very short supply:

“We have 80 years of essentially zero production of neighborhoods with these qualities,” Grant says. “We’ve spent the last 80 years building car-oriented suburbs. Then when the elites decide they want to go back into the city, there’s not enough city to go around.”

This is one reason why supply matters.