1# Allowance for leap seconds added to each time zone file. 2 3# This file is in the public domain. 4 5# This file is generated automatically from the data in the public-domain 6# NIST/IERS format leap-seconds.list file, which can be copied from 7# <https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list> 8# or via a less-secure protocol and with different comments and 9# less volatile last-modified and expiration timestamps, from 10# <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. 11# For more about leap-seconds.list, please see 12# The NTP Timescale and Leap Seconds 13# <https://www.eecis.udel.edu/~mills/leap.html>. 14 15# The rules for leap seconds are specified in Annex 1 (Time scales) of: 16# Standard-frequency and time-signal emissions. 17# International Telecommunication Union - Radiocommunication Sector 18# (ITU-R) Recommendation TF.460-6 (02/2002) 19# <https://www.itu.int/rec/R-REC-TF.460-6-200202-I/>. 20# The International Earth Rotation and Reference Systems Service (IERS) 21# periodically uses leap seconds to keep UTC to within 0.9 s of UT1 22# (a proxy for Earth's angle in space as measured by astronomers) 23# and publishes leap second data in a copyrighted file 24# <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. 25# See: Levine J. Coordinated Universal Time and the leap second. 26# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 27# <https://ieeexplore.ieee.org/document/7909995>. 28 29# There were no leap seconds before 1972, as no official mechanism 30# accounted for the discrepancy between atomic time (TAI) and the earth's 31# rotation. The first ("1 Jan 1972") data line in leap-seconds.list 32# does not denote a leap second; it denotes the start of the current definition 33# of UTC. 34 35# All leap-seconds are Stationary (S) at the given UTC time. 36# The correction (+ or -) is made at the given time, so in the unlikely 37# event of a negative leap second, a line would look like this: 38# Leap YEAR MON DAY 23:59:59 - S 39# Typical lines look like this: 40# Leap YEAR MON DAY 23:59:60 + S 41Leap 1972 Jun 30 23:59:60 + S 42Leap 1972 Dec 31 23:59:60 + S 43Leap 1973 Dec 31 23:59:60 + S 44Leap 1974 Dec 31 23:59:60 + S 45Leap 1975 Dec 31 23:59:60 + S 46Leap 1976 Dec 31 23:59:60 + S 47Leap 1977 Dec 31 23:59:60 + S 48Leap 1978 Dec 31 23:59:60 + S 49Leap 1979 Dec 31 23:59:60 + S 50Leap 1981 Jun 30 23:59:60 + S 51Leap 1982 Jun 30 23:59:60 + S 52Leap 1983 Jun 30 23:59:60 + S 53Leap 1985 Jun 30 23:59:60 + S 54Leap 1987 Dec 31 23:59:60 + S 55Leap 1989 Dec 31 23:59:60 + S 56Leap 1990 Dec 31 23:59:60 + S 57Leap 1992 Jun 30 23:59:60 + S 58Leap 1993 Jun 30 23:59:60 + S 59Leap 1994 Jun 30 23:59:60 + S 60Leap 1995 Dec 31 23:59:60 + S 61Leap 1997 Jun 30 23:59:60 + S 62Leap 1998 Dec 31 23:59:60 + S 63Leap 2005 Dec 31 23:59:60 + S 64Leap 2008 Dec 31 23:59:60 + S 65Leap 2012 Jun 30 23:59:60 + S 66Leap 2015 Jun 30 23:59:60 + S 67Leap 2016 Dec 31 23:59:60 + S 68 69# UTC timestamp when this leap second list expires. 70# Any additional leap seconds will come after this. 71# This Expires line is commented out for now, 72# so that pre-2020a zic implementations do not reject this file. 73#Expires 2026 Jun 28 00:00:00 74 75# Here are POSIX timestamps for the data in this file. 76# "#updated" gives the last time the leap seconds data changed 77# or, if this file was derived from the IERS leap-seconds.list, 78# the last time that file changed in any way. 79# "#expires" gives the first time this file might be wrong; 80# if this file was derived from the IERS leap-seconds.list, 81# this is typically a bit less than one year after "updated". 82#updated 1751846400 (2025-07-07 00:00:00 UTC) 83#expires 1782604800 (2026-06-28 00:00:00 UTC) 84 85# Updated through IERS Bulletin C (https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat) 86# File expires on 28 June 2026 87