Forbes Magazine seems to be addicted to the making of lists, and I have to admit that many of them make pretty good reading. Lots of them are just conversation starters about topics that can’t really be quantified, like “The 20 Most Important Tools Ever,” “The Top 100 Celebrities” and “The Most Livable Cities.” But the annual listing of the Forbes 400 Richest Americans is light on opinions and heavy on data, which means it’s right up my alley. I haven’t delved very deeply into the list beyond the featured Top 20, but there are lots of interesting insights...