Beyond the predictability of physical variation, there is also the unknown probability of a human decision to abolish leap seconds, while also continuing to satisfy the various legal requirements around the world that civil time be tied to the Sun. https://en.wikipedia.org/wiki/Leap_second#Proposal_to_abolish_leap_seconds
Tim N3QE On Thu, Apr 11, 2019 at 3:01 PM Adrian Godwin <[email protected]> wrote: > Thanks. So the current estimate of 13 is towards the high end and variation > is large enough that 40 years with might be sufficiently low that only 1 > rollover is assumed. Not likely to overflow the leap second count early > either. > > > On Thu, Apr 11, 2019 at 3:01 PM Tony Finch <[email protected]> wrote: > > > Adrian Godwin <[email protected]> wrote: > > > > > > How much variation in the rate of leap second insertion is there? > > > > 1972-01-01 - 1992-01-01 : 17 > > 1973-01-01 - 1993-01-01 : 16 > > 1974-01-01 - 1994-01-01 : 16 > > 1975-01-01 - 1995-01-01 : 16 > > 1976-01-01 - 1996-01-01 : 15 > > 1977-01-01 - 1997-01-01 : 15 > > 1978-01-01 - 1998-01-01 : 15 > > 1979-01-01 - 1999-01-01 : 14 > > 1980-01-01 - 2000-01-01 : 14 > > 1981-01-01 - 2001-01-01 : 13 > > 1982-01-01 - 2002-01-01 : 12 > > 1983-01-01 - 2003-01-01 : 11 > > 1984-01-01 - 2004-01-01 : 10 > > 1985-01-01 - 2005-01-01 : 10 > > 1986-01-01 - 2006-01-01 : 9 > > 1987-01-01 - 2007-01-01 : 10 > > 1988-01-01 - 2008-01-01 : 10 > > 1989-01-01 - 2009-01-01 : 9 > > 1990-01-01 - 2010-01-01 : 10 > > 1991-01-01 - 2011-01-01 : 9 > > 1992-01-01 - 2012-01-01 : 8 > > 1993-01-01 - 2013-01-01 : 8 > > 1994-01-01 - 2014-01-01 : 7 > > 1995-01-01 - 2015-01-01 : 6 > > 1996-01-01 - 2016-01-01 : 7 > > 1997-01-01 - 2017-01-01 : 6 > > 1998-01-01 - 2018-01-01 : 6 > > 1999-01-01 - 2019-01-01 : 6 > > 2000-01-01 - 2020-01-01 : 6 > > > > Tony. > > -- > > f.anthony.n.finch <[email protected]> http://dotat.at/ > > Trafalgar: In east, northerly 5 or 6. In west, variable 3 or 4. In east, > > moderate, occasionally rough. in west, moderate, occasionally rough in > > north. > > In east, fair. In west, mainly fair. In east, good. In west, good. > > > > _______________________________________________ > > time-nuts mailing list -- [email protected] > > To unsubscribe, go to > > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > > and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to > http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com > and follow the instructions there. > _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to http://lists.febo.com/mailman/listinfo/time-nuts_lists.febo.com and follow the instructions there.
