In 2008 the property bubble burst in Chicago. It is hard to gauge a recession without some hard numbers. In this case a visual representation gives a powerful view into the scale of the decline in building activity, measured by the total value of building permits by large builders. The visual gives a reference for the scale of the recession. A big thank you to the Chicago’s Open Data Portal for providing the data to work with.

The Data Portal has all the Chicago building permits available online which are a great metric for building activity. I narrowed down the permits to construction activity (elevator repair and fire alarm systems didn’t count) and used Python and Gephi to graph out the connections. Take a look at the result:

Yearly building activity of the largest builders in Chicago, 2006-2012

It was important to filter out smaller builders to have a clear image. The threshold for a builder to make the graph was at least 100 building permits or total permit value of over two million dollars. Each year is scaled to the total value of the building permits for that year, ranging from $8.3 billion in 2006 down to $752 million in 2009 and back up to $4 billion in 2011. Look what happened to John C. Hanna’s activity. In 2006 Hanna’s firm was the most active by properties. In 2007 and 2008 the activity was significantly reduced and failed to make the graph in 2009. By 2010 Hanna was back on the graph and by 2011 was growing again.

If you would like the higher resolution version or a PDF of the image, contact me.