Here, incidentally, is exactly where it would be nice to be able to link to another entry. Assuming for the sake of argument that we want to retain the current pre-standardized-time behavior for Europe/Vaduz, we could change: Zone Europe/Vaduz 0:38:04 - LMT 1894 Jun 1:00 - CET 1981 1:00 EU CE%sT to: Zone Europe/Vaduz 0:38:04 - LMT 1894 Jun => Europe/Zurich where the "=> Europe/Zurich" syntax (that I just made up, and which doubtless could be made much better) says to apply the rules of that zone for the time period of that rule. If you apply a winnowing threshold after June of 1894, the zone would then just become a link; if you don't, it would be a separate zone but would just mirror Europe/Zurich. You could even potentially allow such a line to have an end date, so that you could directly represent "followed all the rules of another zone during ths time range" without duplicating those rules. Without that, applying the DST corrections from 1941 to 1942 to Europe/Vaduz as well requires copying them from Europe/Zurich, which loses the piece of information that they're not confirmed rules specific for Liechtenstein but rather copied rules from Europe/Zurich under the assumption that they were probably the same. You can put that information back in comments, of course, but it still would be nice to be able to represent it in the data format. -- Russ Allbery (rra@stanford.edu) <http://www.eyrie.org/~eagle/>