--Peter Elderson (talk) 11:10, 28 December 2018 (UTC) The remark about survey:date statistics not representing real human usage: I think the antarctica import did not include relations. So the relation statistic in fact does represent real human usage.
check_date:existence and checked_exists:date
Noted it use, although it is problematic. According to check_date=* syntax, it would indicate to be the date when Tag named existence=* was last checked. As there is no such tag at the moment, so it is wrong. If needed, there is checked_exists:date=* which seems to serve the same purpose which is used order of magnitude times more.