Update 2016-12-07

Update 2016-12-07: this is somewhat distorted by family dances, where we occasionally open the hall two hours early and do a family dance followed by a potluck before our regular dance. We've had ~4 of them, and they typically have higher attendance because they attract some people who wouldn't have come otherwise. Instead of trying to figure out what attendance would have been for those nights if we hadn't had the family portion, here's a version of...