Population Growth Raters of American Cities

This is a chart I made recently, actually an update of a chart I made several years ago, but which was really ugly in my 2003 version of excell. I think it would be great to use buildings instead of the filled area. I'll get to that one day. It works to have so many data sets on top of each other because for the most part they follow the same path, enormous early growth followed by much more moderate growth, and in some cases, shrinkage.
We know that these days metropolitan area population numbers are more important that city numbers themselves. What I'm really going for here is an illustration of American history as told by the establishment of our major cities. In the chart you can see the old eastern seaboard cities, the rise of the mid-west, then the west, and then the sun-belt, as well as the hollowing out of rust-belt cities.
City selection is non-scientific, but I've tried to select cities that clearly represent different epochs, regions, or growth patterns.
I hope you enjoy.