I am confused by this vampire framing. “[M]any voters in Wisconsin have a birth year of 1800.” No version of the L2 voter file I have seen reports a birth year of 1800. Instead, the file simply reports missing data for 29% of active registrants. The point of my post is that we do not need to wonder the ages of these voters. There is no mystery here. The WEC publishes monthly counts which show many times more young registrants than L2. As an unrelated point, I would not describe late movement as leading to “error” in our survey, since we were measuring the electorate as of July 22-27 and not predicting what it would be on August 11.