The first graph shows a breakdown of total visits vs. new visitors. This is Google's best guess as to what percentage of traffic is new. I am averaging 660 visits per day, and Google estimates that 85 of them are new. Of course it's not as simple as that, but I am not going to delve into the mechanics of Google Analytics. Others do that far more effectively.
The second graph is Google's estimation of the absolute unique visitors to the blog over the past month. Again, how it determines this is not straightforward enough to delve into here, so the number I am showing may seem a bit puzzling. The answer to the question, "How many people visit the blog?" seems to be AT MOST 3500 in the last month, which is obviously a lot larger than the number of semifinalists. It is conceivable, though highly unlikely, that every 2011 semifinalist has visited this blog in the last month. The most plausible explanation is that some of you have cleared your browser cache or space out your visits to the blog such that Google's tracking mechanism no longer recognizes you as a returning visitor, instead counting you as a unique visitor. My guess is that there are some several hundred of you lurking, with at most a hundred actively commenting. I have no way of confirming this, however, since I've limited my ability to collect that sort of information.
