Congress voted and W signed the bill to extend daylight savings time by four weeks as part of the Energy Policy Act of 2005. This act changed the time change dates in the U.S. to start in 2007. At that time, Daylight Saving Time (DST) will begin on the second Sunday of March, and end the first Sunday of November. As a safety measure, the Secretary shall report to Congress on the impact of this change; Congress retains the right to revert once the Department study is complete.
The long lag time is to allow systems dependent on the current sense of “time” to adjust. This feels like a flashback to 1997, when a woman I knew told me that her daddy said “Why-Two-Kay” was going to be a big deal, and that I'd better prepare for it.
Of course, Y2K was a big deal: the lack of predicted disasters nonwithstanding, I feel much better that Corporate America got behind the bandwagon to make things “right”. I know a dozen folks who made their bones in technology during that time period (most are still in the business). It was this effort and these people that ensured we'd hold the disasters at bay.
Now, none of my code was at risk of the two-digit year: I knew better coming out of grammar school not to represent a year with only two digits. This is not intended as an insult to the folks who wrote in COBOL; I understand those two additional bytes meant a lot to a program and memory. I had the luxury of much more computing power and far better tools.
Flash forward to the present day. I believe Corporate America needs to take a good look at their code with the impending DST changes in mind: this will prove to be an important effort, albeit easier now, with updated code and modern tools.
The change also presents an interesting argument for encapsulating date / time libraries, just like we encapsulate business processes. If “time” can change on a (congressional) whim, we need to apply the same discipline we apply to changing business processes, responding with rules and properties, and not code rewrites.
For the historically-biased, here are a few links:
New York Daily News: “Another Month of Daylight”
StandardTime: “Why”
InfoPlease gives us a world-wide view: “Daylight Saving Time”