Robert Elz <kre@munnari.oz.au> writes:
Do you really believe that almost anyone (members of this list perhaps excepted) actually changes their clock at the precise instant that DST (or summer time, or whatever it gets called in different areas) actually changes.
Yes, I do. Many people in this country no longer use watches; they use cell phones to tell time. And cell phones did change at 02:00 in Wisconsin on April 2; see <http://www.wisbusiness.com/index.iml?Article=58272>. I myself prefer an old-fashioned pocket watch, but I've observed that my students, whose ages are typically around 20, use cell phones or laptops to tell time just as often as they use watches -- perhaps even more so. Sales of cheap watches reportedly declined 10% last year in the US, most likely due to the popularity of telling time by cell phone; see <http://www.news-journalonline.com/NewsJournalOnline/News/Headlines/frtHEAD03...>. I imagine that people who have to log times (nurses, doctors, police officers, and fire departments, for example) make sure their clocks are close to the consensus time. These days no doubt a lot of this is automated (mostly by our work, by Microsoft's, and by the cell phone companies') but that still counts. I did consult some sources in Wisconsin for what people actually do, and they agreed that 02:00 was the time people switched. See, for example, Bob Petrie, Locals prepare to lose sleep, gain daylight, Sheboygan Press (2006-04-01) <http://www.htrnews.com/apps/pbcs.dll/article?AID=/20060401/SHE0101/604010508...>
More likely to be relevant would be what time the radio stations announce during the "different" hour
I'd be surprised if radio-station time announcements in Wisconsin differed materially from the federal daylight-saving rules.