Paul Eggert wrote:
Yes, I'd thought about that. Maintaining the population figures would be a bit of a pain (and another source of arguments!),
It doesn't require much maintenance. We don't really need to update them, because the relative population figures only change slowly. It should suffice to collect a single figure per location, the estimated population for a common reference date. I suggest a nominal reference date of 2010 (-01-01T00:00:00Z, for the picky). We can think about switching to a new reference date in 2020. (There's a thought here to the possible future extension to sort on population as it was at the user's choice of historical era, for which population figures at decadal intervals should be adequate.) As a test, I just picked five entries from tz2013d zone.tab at random, and looked up the locations on Wikipedia. (Indian/Maldives, Asia/Almaty, Asia/Vientiane, America/Martinique, Atlantic/Reykjavik.) In all five cases the infobox at the top of the article gives a recent population figure, with date, dates ranging from 2007-01-01 to 2013-02-01. Three out of five gave a citation specifically for the population figure. Using those figures as-is should suffice for our purposes, or we can crudely correct for the variable dates by applying an exponential model of short-term population growth. I'd be inclined to stick the population figures in the zone source files, probably as a magic comment to avoid breaking anyone's zic. An automated process can generate a .tab from that. -zefram