[tz] South America / Brazil / Brasilia GMT(-3:00) in the timezone database

Brian Inglis Brian.Inglis at SystematicSw.ab.ca
Tue Mar 5 20:52:11 UTC 2019

On 2019-03-05 02:49, rhiccarddo rcd wrote:
> If the "normally" parameter used to define which city will serve as a reference
> for the time zone within the operating system is that of the most populous city,
> I ask: Why are there only seven locations randomly registered between cities and
> states, that exists even more than one city of the same state (state of Pará for
> example) among the seven currently registered, since Brazil has 27 states and
> 5570 municipalities and what, at least should be registered is the federal
> capital, whose name is Brasilia, reference for more than two hundred million
> Brazilians as official time?

The most populous city in a time zone whose clocks have agreed since 1970 may
now also be in a different country, and once a city has been designated, is
unlikely to be changed, unless there are changes in the history of the clocks; see:


> The attached images serve to illustrate the above subject.

Those images are of user interfaces provided by some software suppliers.
Please refer any issues with those interface displays to those software
suppliers: that is their interface decision.
Time zones provide a technical means of supporting time zones and maintaining
the underlying information.
Some suppliers use their own time zone sources and data, notably MS Windows OS,
not that available at IANA, and some suppliers modify the IANA information for
greater compatibility with their app and user bases.

Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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