Implications of Proposed Changes to Daylight Saving Time in the United States

This past week, I’ve contacted and spoken with several legislators on the plethora of proposed changes to use of daylight saving time around the States. I even had a call from my friend, Rich Kaplan, the new CEO over at the Microsoft Alumni Network, reminiscing over a few of these recent moves. The efforts fall under two main proposals: to move their state to perpetual daylight saving time, as is the case in Florida, Mississippi (died in committee) and New Mexico*; or, to move to permanent standard time, as proposed in Alaska, Oregon, South Dakota, Texas, Utah** and Washington. (I recently heard that the bill to adopt daylight saving time in Arizona has been held up by the House leadership, effectively dead in committee.) I’m not sure what will happen in Florida and New Mexico, given that the United Sates Code (15 U.S.C. §6(IX)(260-7)) stipulates that states shall either implement the semiannual daylight saving time changes or remain on standard time throughout the year.

Asked what I worry about this now, I recalled Winston Churchill’s quote:

“Let our advance worrying become advance thinking and planning.”

I appreciate that the legislators in several states have thoughtfully called for such changes to take effect in 2017 or later (2021, in Oregon). But a few, like Texas and Washington, would have the changes as early as fall of 2015. Without adequate time to react, such changes can be challenging for individuals to manage and for companies to support. Not a very united effort in the States as a whole.

That’s why Microsoft has recommended (via the tab “Microsoft Policy in Response to DST/TZ Requests” in the left nav of the page) that governments take at least one year from the time the proposals are enacted into law for the change to occur. As an example, I look to the timeline provided in the Energy Policy Act of 2005, outlining sweeping changes to daylight saving time in the United States, that allowed for nearly a year and a half before the change was implemented.

But just as important as the time needed to implement these changes, also consider the technical implications of moving to permanent daylight saving time rather than moving solely to standard time.

imageAs noted in my last post, a few states have proposed to move to year-round standard time and drop daylight saving altogether, a fairly straight forward approach. Given that many devices (PCs, phones, tablets and services) allow you to select whether or not products use a daylight saving time offset, shifting the device between daylight saving and standard time twice a year is fairly simple, and turning off the automated change is quite simple. In Windows, you may check the option for the device to “Automatically adjust clock for Daylight Saving Time” if your time zone observes daylight saving time and you want your computer’s clock to be adjusted automatically when daylight saving time changes. (In the States, that’s on March 8, 2015.)

But moving to permanent daylight saving time may not be easily implemented on devices that are no longer supported and don’t receive updated rules: this includes computers, mobile phones, embedded devices, connected systems and services. For instance, older operating systems that are out of support (such as the venerable Windows XP) no longer receive updates which include the updated set of worldwide time zones and daylight saving offsets.

More information than you’ll care to remember is available in KB 914387, How to configure daylight saving time for Microsoft Windows operating systems.


* – an added twist: New Mexico, today in the Mountain time zone, would move in the current proposed legislation to the central time zone and be known as “mountain daylight savings time.”

** – Feb 9, 2015: Latest reports indicate Senate Resolution 1 died in committee.


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Available now: August 2014 cumulative time zone update for Windows operating systems

The August 2014 cumulative time zone update for Windows operating systems has been released and is available as Microsoft KB 2981580. As noted, the update replaces the previous December 2013 CU (KB 2904266) and includes all the time zone and daylight saving time changes released as hotfixes after update KB 2904266 was released.

The following changes were made since the previous Windows cumulative time zone update:

  • Jordan Standard Time: For 2014 and onward, Jordan has changed its DST Start time from the last Thursday in March at midnight to the last Friday in March at 1 A.M., and its DST End time from the last Friday in October at 1 A.M to the last Friday in October at midnight. (
  • Fiji Standard Time: For 2014 only, Fiji has changed its DST End time from January 19 at 3 A.M. to January 19 at 2 A.M. (    
  • Paraguay Standard Time: For 2014 and onward, Paraguay has changed its DST End date from the second Sunday in April to the fourth Sunday in March. (    
  • Turkey Standard Time: For 2014 only, Turkey has changed its DST Start time from March 30 at 3 A.M. to March 31 at 3 A.M. (
  • Pacific SA Standard Time: For 2014 only, the DST Start time is changed from the Last Saturday in April (April 26) at midnight to the Last Saturday in April (April 26) at 11 P.M., and the DST End time is changed from the first Saturday in September (Sept. 6) at midnight to First Sunday in September (Sept. 7) at 1 A.M. (    
  • Egypt Standard Time: For 2014, Egypt has set its DST Start time at Thursday, May 15 at one minute before midnight, and its DST End time at Thursday, September 25 at one minute before midnight. (    
  • Line Islands Standard Time: A new time zone for Kiritimati Island (UTC+14) is added. (    
  • SA Pacific Standard Time: Starting on November 10, 2013, the display name is changed from “(UTC-05:00) Bogota, Lima, Quito” to “(UTC-05:00) Bogota, Lima, Quito, Rio Branco.” (   

Russian Federation Permanently Switches to Winter Time October 26, 2014: Changes to Microsoft Products

(Update 082214: Please see the new post Update on Windows support for new Russian Time Zones with more information on the upcoming update.)

MP900385402[1]Back in 2011, I wrote on the Microsoft corporate blog about the of daylight saving time in the Russian Federation. Then in 2012, I noted Russia considered a return to Winter Time in 2012.

If my very poor knowledge of Russian proverbs is correct: Бог тро́ицу лю́бит. In other words, “Third time’s a charm.” (I’m also reminded of the saying, “There was a time they loved an accordionist, and now the time has come where they love a tractor driver.” but that’s a different story.)

Since then, there’s been a number of reports of discussions in Russia about a shift away from the changes to time zones and daylight saving time offsets in the Russian Federation. Over the summer (here in the northern hemisphere) the Russian State Duma passed a proposal which was signed into law by President Putin, which outlines the plan to change all of the time zones in the Federation. (A highlight from the venerable BBC is available here.) The changes will take effect October 26, 2014, and essentially moves many existing time zones back one hour, and create two new time zones. These new time zones will not observe daylight saving time (aka DST).

(You may view the Federal Law 431985-6, noting the return to winter time and to use 11 time zones in Russia at and with the amendments to the Federal Law on time available here.)

We were aware of this proposal and have worked closely with representatives in the country to prepare our products and services for the update. For our customers and partners worldwide, this means there are some things to be aware of, and in some cases, work to do to prepare for this change. We have a preliminary set of new display names for the new time zones to use with the new Russian Time Zones (aka RTZ):


Name of Time Zone (Current)

Display Name


Kaliningrad Standard Time

(UTC+02:00) Kaliningrad (RTZ1)


Russian Standard Time

(UTC+03:00) Moscow, St. Petersburg, Volgograd (RTZ2)



(UTC+04:00) Izhevsk, Samara (RTZ3)


Ekaterinburg Standard Time

(UTC+05:00) Ekaterinburg (RTZ4)


N. Central Asia Standard Time

(UTC+06:00) Novosibirsk (RTZ5)


North Asia Standard Time

(UTC+07:00) Krasnoyarsk (RTZ6)


North Asia East Standard Time

(UTC+08:00) Irkutsk (RTZ7)


Yakutsk Standard Time

(UTC+09:00) Yakutsk (RTZ8)


Vladivostok Standard Time / Magadan Standard Time

(UTC+10:00) Vladivostok, Magadan (RTZ9)



(UTC+11:00) Chokurdakh (RTZ10)


Kamchatka Standard Time (obsolete)

(UTC+12:00) Anadyr, Petropavlovsk-Kamchatsky (RTZ11)

(Often, time zone names are referenced by developers through API calls (“GetTimeZoneInformation”) as noted on here on MSDN.)

We have outlined the release schedule for the update prior to the change, which we’ll publish shortly on our Daylight Saving Time Help and Support Center (at and on our Daylight Saving Time & Time Zone Blog.

If you’ve read previous posts, you’ll recall that our Windows team in OSG follows DST and TZ changes globally and provides guidance to all product and services teams on the changes. Most applications and services reference the underlying Windows OS for their TZ and DST rules, with some exceptions. This change in Russia has the potential for worldwide impacts on time references for multinational customers, and so the recommendation will be for all customers to apply the updates to currently supported products. Updates will be important not only for users in Russia but for connected systems around the world. (While Microsoft’s Services infrastructure will be updated to reflect these DST changes, it’s important that your computers — both clients and servers that connect to and interact with these services — should have the Windows DST updates applied in order to ensure data integrity.)

Which reminds me: we have also outlined recommendations to help achieve more seamless transitions to new DST and time zone policies. (More information is also available at

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The Pros and Cons (or costs) around Daylight Saving Time changes

Yesterday, the Detroit Free Press presented two views on the changes to the schedule on daylight saving time in 2007: one that it saves energy and another that it doesn’t.  These read like a Point-Counterpoint discussion on ABC News, and my unscientific review of articles yesterday points to a majority of opinion that DST doesn’t save much if any energy or money.  In fact, it looks like it increases costs for businesses and headaches for IT Pros and systems administrators.

[Note: I wrote this article on Sunday after verifying that in fact the world continued to spin on its axis after the clocks all moved forward in the US and Canada.  Just posting it now prior to heading off to a working lunch meeting in a different building on campus.] 

The first is an article is by U.S. Representative Fred Upton (R-St. Joseph), who represents Michigan’s 6th Congressional District (  Along with Ed Markey (D-Mass.), representative Upton was one of the two authors of the extension to daylight saving time (which varies with calendars rather than a standard four week extension as Upton describes) in the US Department of Energy’s Energy Policy Act of 2005

“We based the extension on sound science — closely examining the Department of the Navy’s sun tables to determine that a four-week extension would maximize our nation’s energy savings.

“Fast forward to today. The American Council for an Energy-Efficient Economy estimates that the cumulative benefit of the four-week extension through 2020 will be a saving of approximately $4.4 billion and a reduction of carbon emissions by 10.8 million metric tons, cutting harmful greenhouse gases.

“Not only is extending daylight saving time an issue of conservation, it is also one of safety. Studies by a leading auto safety group have shown that extending daylight saving will save dozens of lives on our nation’s roads each year. Most accidents occur at dusk, but with the extended DST, our kids will have returned home from school and many folks will have completed their evening commute by sundown.”

The Free Press editorial, “Extended daylight saving time should be reset — it doesn’t save energy”rebuts that the first year with the new DST rules doesn’t save energy… but brings additional headaches…

“What it will do, for the next month or so, is keep sending kids out in the dark to wait for the school bus, make them less alert for the first hour of class and, as evening daylight keeps getting longer, less inclined to come inside to do homework or study.

“Farmers don’t like it much, nor do early morning exercisers and all those people who never seem to really wake up until daylight is coming in through the windows. The later switch in the fall also means little trick-or-treaters miss the fun of setting out on Halloween in the dark.”

Speaking of rug rats in search of sugary treats (we have two at home)… as I mentioned in “What do candy, Microsoft products and Congress have in common?” the change was of potential interest to one industry in particular: candy manufacturers, who reportedly lobbied for an extension to DST: this sunny extension will allow trick-or-treaters to scream “trick-or-treat” and collect candy for an additional hour.

Last fall, I saw a reference to a preliminary study for the California Energy Commission that showed savings during peak hours of 3.4 percent in March and 2.8 percent in November in 2007.  But again that seems to be a minority view: as I noted in a post last week, more recent analysis of the changes in Indiana concluded that DST doesn’t necessarily save energy (as noted here on NPR radio’s site).  The study in the report found that overall, Indiana households spent on average about $3.73 per household per year more on energy due to daylight saving time:…

“Against intuition and contrary to the entire point of government policy, the study found that daylight saving time resulted in an $8.6 million increase in spending on residential electricity.”

Also, I have not seen any follow up from the Dept. of Energy (DOE): as you may recall, in the Energy Policy Act of 2005, Congress retained the right to revert daylight saving time to its previous schedule as soon as the DOE had completed its assessment of the change in 2007.  I have only read passing commentary from the DOE, such as that noted in this link...

“Megan Barnett, a spokeswoman for the U.S. Department of Energy, said the jury still is out on the exact savings nationwide of extending DST.  “We did a preliminary analysis, based on decades-old information, that indicates a very small, or fractional amount, of energy savings,” she said.

My personal suggestion? 

Leave the 2007 DST change as it is.  Live with the new DST rules in the US and Canada. Don’t flip-flop with calendar changes. 

Or if you’re going to make a move to the entry and exit dates on DST, just make one final move and leave it at that.

Countries should closely consider the other incremental costs associated with such changes — in addition to the potential for energy savings — lest they discover after the fact that a “simple time zone change” or “small modified entry/exit date to their observance of DST” impacts more broad than within their own boarders.  Apparently Venezuela had that experience and found that making a sudden change so quickly or with little impact to industry is difficult, having delayed the move to a new time zone not once but six or seven times by my count. 

And if you are going to make a change, ensure that the DOE, Congress — or some government agency (including the venerable DOE, where the change originated before being signed into law) — advertises and promotes the change well in advance as we have seen with the transition to digital TV in the States.

None of this accounts for the changes consumers and professionals must make in their homes and in their businesses. In the technology industry, these changes are cause for many impacts in several areas, from updating computers and business systems to adjusting clocks and devices that are not able to keep up with these changes.

More on how we’re dealing with these changes later this week.  Now, on to lunch.

Tags: Microsoft, Indiana, Matthew Kotchen, Daylight Saving Time, Daylight Savings Time, RSS,DST. 3,530,000; 6,950,000; 649,000+