Thank you. This is something I have been trying to say as well. The db format should allow us to collect historical tz information for any region, even locations that are only different before 1970. This is of use for those that do historical time-of-day research in any field, such as astronomy. Eventually all locations on earth, going backward, revert to local solar (sundial) time, so we only need to collect data which is other than local solar time, generally going back to the dates of implementation of local mean time for various locations. Obviously, such a collection can never be complete, like any historical data, but it does provide information which is useful to some, and constantly improving. ----- Original Message ----- From: Christos Zoulas via tz [mailto:tz@iana.org] To: "Time zone mailing list" <tz@iana.org> Sent: Sat, 9 Jul 2022 07:01:08 -0400 Subject: Re: [tz] Moving more zones to 'backzone' I view maintaining the pre-1970 data as an exercise in improving the historical record of timezone information. Historians don't simply discard information when they are not certain about its accuracy. They constantly work to make it better. In extreme cases it is called https://en.wikipedia.org/wiki/Historical_revisionism. I don't see any other group of people trying to do this work, so like it or not we are the best positioned group to maintain this information right now. I believe that we should provide the best information to our knowledge instead of giving up and discarding it because of convenience. I also agree with kre that the arcane zic format needs to be redesigned to ease maintenance. Best, christos