I must admit, I’ve been extremely lazy about reading Visualizing Data or even updating this blog… but, this post should make up for it.
For the uninitiated, Case-Shiller tracks home prices in 20 metro areas. As WSJ states, “[the index has] a base value of 100 in January 2000. So a current index value of 150 translates to a 50% appreciation rate since January 2000 for a typical home located within the metro market.”
This program graphs the history of each city’s home price index. Not satisfied with just a plain-old graph, I added some aesthetic and functional features. The 20-city composite is shown for reference. Moving the mouse over the graph will highlight and display the index for a given point in time. Clicking the mouse will advance to another city.
The graph’s data comes from a static CSV which I slightly hand-modified from the original XLS spreadsheet.
It’s interesting the number of little things I find missing or bothersome. For example, I’d like to use curveVertex()
vertex() for a smoother line curve, but by nature it doesn’t display the first and last data points. Fortunately there are enough data points and few large jumps/drops so the graph does not appear jagged. I could go on…
Taking a break from the book and making something useful has been fun.