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 format leap-seconds.list file, which can be copied from 7# <ftp://ftp.nist.gov/pub/time/leap-seconds.list> 8# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. 9# For more about leap-seconds.list, please see 10# The NTP Timescale and Leap Seconds 11# <https://www.eecis.udel.edu/~mills/leap.html>. 12 13# The rules for leap seconds are specified in Annex 1 (Time scales) of: 14# Standard-frequency and time-signal emissions. 15# International Telecommunication Union - Radiocommunication Sector 16# (ITU-R) Recommendation TF.460-6 (02/2002) 17# <https://www.itu.int/rec/R-REC-TF.460-6-200202-I/>. 18# The International Earth Rotation and Reference Systems Service (IERS) 19# periodically uses leap seconds to keep UTC to within 0.9 s of UT1 20# (a proxy for Earth's angle in space as measured by astronomers) 21# and publishes leap second data in a copyrighted file 22# <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. 23# See: Levine J. Coordinated Universal Time and the leap second. 24# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 25# <https://ieeexplore.ieee.org/document/7909995>. 26 27# There were no leap seconds before 1972, as no official mechanism 28# accounted for the discrepancy between atomic time (TAI) and the earth's 29# rotation. The first ("1 Jan 1972") data line in leap-seconds.list 30# does not denote a leap second; it denotes the start of the current definition 31# of UTC. 32 33# All leap-seconds are Stationary (S) at the given UTC time. 34# The correction (+ or -) is made at the given time, so in the unlikely 35# event of a negative leap second, a line would look like this: 36# Leap YEAR MON DAY 23:59:59 - S 37# Typical lines look like this: 38# Leap YEAR MON DAY 23:59:60 + S 39Leap 1972 Jun 30 23:59:60 + S 40Leap 1972 Dec 31 23:59:60 + S 41Leap 1973 Dec 31 23:59:60 + S 42Leap 1974 Dec 31 23:59:60 + S 43Leap 1975 Dec 31 23:59:60 + S 44Leap 1976 Dec 31 23:59:60 + S 45Leap 1977 Dec 31 23:59:60 + S 46Leap 1978 Dec 31 23:59:60 + S 47Leap 1979 Dec 31 23:59:60 + S 48Leap 1981 Jun 30 23:59:60 + S 49Leap 1982 Jun 30 23:59:60 + S 50Leap 1983 Jun 30 23:59:60 + S 51Leap 1985 Jun 30 23:59:60 + S 52Leap 1987 Dec 31 23:59:60 + S 53Leap 1989 Dec 31 23:59:60 + S 54Leap 1990 Dec 31 23:59:60 + S 55Leap 1992 Jun 30 23:59:60 + S 56Leap 1993 Jun 30 23:59:60 + S 57Leap 1994 Jun 30 23:59:60 + S 58Leap 1995 Dec 31 23:59:60 + S 59Leap 1997 Jun 30 23:59:60 + S 60Leap 1998 Dec 31 23:59:60 + S 61Leap 2005 Dec 31 23:59:60 + S 62Leap 2008 Dec 31 23:59:60 + S 63Leap 2012 Jun 30 23:59:60 + S 64Leap 2015 Jun 30 23:59:60 + S 65Leap 2016 Dec 31 23:59:60 + S 66 67# UTC timestamp when this leap second list expires. 68# Any additional leap seconds will come after this. 69# This Expires line is commented out for now, 70# so that pre-2020a zic implementations do not reject this file. 71#Expires 2021 Jun 28 00:00:00 72 73# POSIX timestamps for the data in this file: 74#updated 1467936000 (2016-07-08 00:00:00 UTC) 75#expires 1624838400 (2021-06-28 00:00:00 UTC) 76 77# Updated through IERS Bulletin C60 78# File expires on: 28 June 2021 79