Table 5. Differences between the normalized frequencies of EAL and TAI, up to March 2017 Date MJD [f(EAL)- f(TAI)] x 10**-13 1977 Jan 1 - 1977 Apr 26 43144 - 43259 10.0 1977 Apr 26 - 1977 Jun 25 43259 - 43319 9.8 1977 Jun 25 - 1977 Aug 24 43319 - 43379 9.6 1977 Aug 24 - 1977 Oct 23 43379 - 43439 9.4 1977 Oct 23 - 1978 Oct 28 43439 - 43809 9.2 1978 Oct 28 - 1979 Jun 25 43809 - 44049 9.0 1979 Jun 25 - 1979 Aug 24 44049 - 44109 8.8 1979 Aug 24 - 1979 Oct 23 44109 - 44169 8.6 1979 Oct 23 - 1982 Apr 30 44169 - 45089 8.4 1982 Apr 30 - 1982 Jun 29 45089 - 45149 8.2 1982 Jun 29 - 1982 Aug 28 45149 - 45209 8.0 1982 Aug 28 - 1984 Feb 29 45209 - 45759 7.8 1984 Feb 29 - 1987 Apr 24 45759 - 46909 8.0 1987 Apr 24 - 1987 Dec 30 46909 - 47159 8.0125 1987 Dec 30 - 1989 Jun 22 47159 - 47699 8.0 1989 Jun 22 - 1989 Dec 29 47699 - 47889 7.95 1989 Dec 29 - 1990 Feb 27 47889 - 47949 7.90 1990 Feb 27 - 1990 Apr 28 47949 - 48009 7.85 1990 Apr 28 - 1990 Jun 27 48009 - 48069 7.80 1990 Jun 27 - 1990 Aug 26 48069 - 48129 7.75 1990 Aug 26 - 1991 Feb 22 48129 - 48309 7.70 1991 Feb 22 - 1991 Apr 23 48309 - 48369 7.625 1991 Apr 23 - 1991 Aug 31 48369 - 48499 7.55 1991 Aug 31 - 1991 Oct 30 48499 - 48559 7.50 1991 Oct 30 - 1992 Apr 27 48559 - 48739 7.45 1992 Apr 27 - 1992 Jun 26 48739 - 48799 7.40 1992 Jun 26 - 1993 Apr 22 48799 - 49099 7.35 1993 Apr 22 - 1995 Feb 21 49099 - 49769 7.40 1995 Feb 21 - 1995 Apr 22 49769 - 49829 7.39 1995 Apr 22 - 1995 Jun 21 49829 - 49889 7.38 1995 Jun 21 - 1995 Aug 30 49889 - 49959 7.37 1995 Aug 30 - 1995 Oct 29 49959 - 50019 7.36 1995 Oct 29 - 1995 Dec 28 50019 - 50079 7.35 1995 Dec 28 - 1996 Feb 26 50079 - 50139 7.34 1996 Feb 26 - 1996 Apr 26 50139 - 50199 7.33 1996 Apr 26 - 1996 Jun 30 50199 - 50264 7.32 1996 Jun 30 - 1996 Aug 29 50264 - 50324 7.31 1996 Aug 29 - 1996 Oct 28 50324 - 50384 7.295 1996 Oct 28 - 1996 Dec 27 50384 - 50444 7.280 1996 Dec 27 - 1997 Feb 25 50444 - 50504 7.265 1997 Feb 25 - 1997 Apr 26 50504 - 50564 7.250 1997 Apr 26 - 1997 Jun 30 50564 - 50629 7.230 1997 Jun 30 - 1997 Aug 29 50629 - 50689 7.210 1997 Aug 29 - 1997 Oct 28 50689 - 50749 7.190 1997 Oct 28 - 1997 Dec 27 50749 - 50809 7.170 1997 Dec 27 - 1998 Jan 31 50809 - 50844 7.160 1998 Jan 31 - 1998 Feb 25 50844 - 50869 7.150 1998 Feb 25 - 1998 Mar 27 50869 - 50899 7.140 1998 Mar 27 - 1999 Feb 25 50899 - 51234 7.130 1999 Feb 25 - 1999 Dec 27 51234 - 51539 7.140 1999 Dec 27 - 2000 May 30 51539 - 51694 7.130 2000 May 30 - 2000 Sep 27 51694 - 51814 7.120 2000 Sep 27 - 2000 Nov 26 51814 - 51874 7.110 2000 Nov 26 - 2001 Jan 30 51874 - 51939 7.100 2001 Jan 30 - 2001 Apr 30 51939 - 52029 7.090 2001 Apr 30 - 2001 Jul 29 52029 - 52119 7.080 2001 jul 29 - 2001 Sep 27 52119 - 52179 7.070 2001 Sep 27 - 2001 Nov 26 52179 - 52239 7.060 2001 Nov 26 - 2002 Jan 30 52239 - 52304 7.050 2002 Jan 30 - 2002 Mar 31 52304 - 52364 7.040 2002 Mar 31 - 2002 Jun 30 52364 - 52424 7.030 2002 Jun 30 - 2002 Jul 29 52424 - 52484 7.020 2002 Jul 29 - 2002 Sep 27 52484 - 52544 7.010 2002 Sep 27 - 2002 Nov 26 52544 - 52604 7.000 2002 Nov 26 - 2003 Jan 30 52604 - 52669 6.990 2003 Jan 30 - 2003 Mar 31 52669 - 52729 6.980 2003 Mar 31 - 2003 May 30 52729 - 52789 6.970 2003 May 30 - 2003 Aug 28 52789 - 52909 6.960 2003 Sep 27 - 2003 Nov 26 52909 - 52969 6.950 2003 Nov 26 - 2004 Jan 30 52969 - 53034 6.940 2004 Jan 30 - 2004 Mar 30 53034 - 53094 6.930 2004 Mar 30 - 2004 May 29 53094 - 53154 6.920 2004 May 29 - 2004 Jun 28 53154 - 53184 6.910 2004 Jun 28 - 2004 Jul 28 53184 - 53214 6.904 2004 Jul 28 - 2004 Dec 30 53214 - 53369 6.899 2004 Dec 30 - 2005 Feb 28 53369 - 53429 6.895 2005 Feb 28 - 2005 Mar 30 53429 - 53459 6.891 2005 Mar 30 - 2005 Apr 29 53459 - 53489 6.888 2005 Apr 29 - 2005 May 29 53489 - 53519 6.886 2005 Feb 28 - 2005 Mar 30 53429 - 53459 6.891 2005 Mar 30 - 2005 Apr 29 53459 - 53489 6.888 2005 Apr 29 - 2005 May 29 53489 - 53519 6.886 2005 May 29 – 2005 Jun 28 53519 - 53549 6.884 2005 Jun 28 - 2005 Jul 28 53549 - 53579 6.878 2005 Jul 28 - 2005 Aug 27 53579 - 53609 6.876 2005 Aug 27 - 2005 Sep 26 53609 - 53639 6.870 2005 Sep 26 - 2005 Oct 31 53639 - 53674 6.868 2005 Oct 31 - 2005 Nov 30 53674 - 53704 6.862 2005 Nov 30 - 2005 Dec 30 53704 - 53734 6.856 2005 Dec 30 - 2006 Jan 29 53734 - 53764 6.850 2006 Jan 29 - 2006 Feb 28 53764 - 53794 6.844 2006 Feb 28 - 2006 Mar 30 53794 - 53824 6.838 2006 Mar 30 - 2006 Apr 29 53824 - 53854 6.832 2006 Apr 29 - 2006 May 29 53854 - 53884 6.826 2006 May 29 - 2006 Jun 28 53884 - 53914 6.823 2006 Jun 28 - 2006 Jul 28 53914 - 53944 6.823 2006 Jul 28 - 2006 Aug 27 53944 - 53974 6.820 2006 Aug 27 - 2006 Sep 26 53974 – 54004 6.820 2006 Sep 26 - 2006 Oct 31 54004 - 54039 6.817 2006 Oct 31 - 2006 Nov 30 54039 - 54069 6.817 2006 Nov 30 - 2006 Dec 30 54069 - 54099 6.812 2006 Dec 30 - 2007 Jan 29 54099 - 54129 6.806 2007 Jan 29 - 2007 Feb 28 54129 - 54159 6.802 2007 Feb 28 – 2007 Mar 30 54159 - 54189 6.802 2007 Mar 30 – 2007 Apr 29 54189 - 54219 6.802 2007 Apr 29 – 2007 May 29 54219 - 54249 6.802 2007 May 29 – 2007 Jun 28 54249 – 54279 6.799 2007 Jun 28 – 2007 Jul 28 54279 – 54309 6.796 2007 Jul 28 – 2007 Aug 27 54309 – 54339 6.793 2007 Aug 27 – 2007 Sep 26 54339 – 54369 6.790 2007 Sep 26 – 2007 Oct 31 54369 – 54404 6.787 2007 Oct 31 – 2007 Nov 30 54404 – 54434 6.784 2007 Nov 30 – 2007 Dec 30 54434 – 54464 6.779 2007 Dec 30 – 2008 Jan 29 54464 – 54494 6.776 2008 Jan 29 – 2008 Feb 28 54494 – 54524 6.772 2008 Feb 28 – 2008 Mar 29 54524 – 54554 6.769 2008 Mar 29 – 2008 Apr 28 54554 – 54584 6.766 2008 Apr 28 – 2008 May 28 54584 – 54614 6.763 2008 May 28 – 2008 Jun 27 54614 – 54644 6.758 2008 Jun 27 – 2008 Jul 27 54644 – 54674 6.753 2008 Jul 27 – 2008 Aug 31 54674 – 54709 6.750 2008 Aug 31 – 2008 Sep 30 54709 – 54739 6.747 2008 Sep 30 – 2008 Oct 30 54739 – 54769 6.742 2008 Oct 30 – 2008 Nov 29 54769 – 54799 6.739 2008 Nov 29 – 2008 Dec 29 54799 – 54829 6.736 2008 Dec 29 – 2009 Jan 28 54829 – 54859 6.731 2009 Jan 28 – 2009 Feb 27 54859 – 54889 6.726 2009 Feb 27 – 2009 Mar 29 54889 – 54919 6.721 2009 Mar 29 – 2009 Apr 28 54919 – 54949 6.716 2009 Apr 28 - 2009 May 28 54949 – 54979 6.711 2009 May 28 - 2009 Jun 27 54979 – 55009 6.706 2009 Jun 27 - 2009 Jul 27 55009 – 55039 6.701 2009 Jul 27 - 2009 Aug 31 55039 – 55074 6.696 2009 Aug 31 - 2009 Sep 30 55074 – 55104 6.691 2009 Sep 30 - 2009 Oct 30 55104 – 55134 6.686 2009 Oct 30 - 2009 Nov 29 55134 – 55164 6.681 2009 Nov 29 - 2009 Dec 29 55164 – 55194 6.676 2009 Dec 29 - 2010 Jan 28 55194 – 55224 6.671 2010 Jan 28 - 2010 Feb 27 55224 – 55254 6.666 2010 Feb 27 - 2010 Mar 29 55254 – 55284 6.661 2010 Mar 29 - 2010 Apr 28 55284 – 55314 6.656 2010 APR 28 - 2010 MAY 28 55314 - 55344 6.651 2010 MAY 28 - 2010 JUN 27 55344 - 55374 6.645 2010 JUN 27 - 2010 JUL 27 55374 - 55404 6.639 2010 JUL 27 - 2010 AUG 26 55404 - 55434 6.633 2010 AUG 26 - 2010 SEP 30 55434 - 55469 6.626 2010 SEP 30 - 2010 OCT 30 55469 - 55499 6.619 2010 OCT 30 - 2010 NOV 29 55499 - 55529 6.612 2010 NOV 29 - 2010 DEC 29 55529 - 55559 6.605 2010 DEC 29 – 2011 JAN 28 55559 - 55589 6.598 2011 JAN 28 – 2011 FEB 27 55589 - 55619 6.591 2011 FEB 27 – 2011 MAR 29 55619 - 55649 6.584 2011 MAR 29 - 2011 APR 28 55649 - 55679 6.577 2011 APR 28 - 2011 MAY 28 55679 – 55709 6.570 2011 MAY 28 - 2011 JUN 27 55709 - 55739 6.563 2011 JUN 27 - 2011 JUL 27 55739 – 55769 6.556 2011 JUL 27 - 2011 AUG 31 55769 - 55804 6.551 2011 AUG 31 - 2011 SEP 30 55804 – 55834 6.546 2011 SEP 30 - 2011 OCT 30 55834 – 55864 6.541 2011 OCT 30 - 2011 NOV 29 55864 – 55894 6.536 2011 NOV 29 - 2011 DEC 29 55894 – 55924 6.531 2011 DEC 29 - 2012 JAN 28 55924 – 55954 6.526 2012 JAN 28 - 2012 FEB 27 55954 – 55984 6.521 2012 FEB 27 - 2012 MAR 28 55984 – 56014 6.516 2012 MAR 28 - 2012 APR 27 56014 – 56044 6.511 2012 APR 27 - 2012 MAY 27 56044 - 56074 6.506 2012 MAY 27 - 2012 JUN 26 56074 - 56104 6.501 2012 JUN 26 - 2012 JUL 31 56104 - 56139 6.496 2012 JUL 31 - 2012 AUG 30 56139 - 56169 6.491 2012 AUG 30 - 2012 SEP 29 56169 - 56199 6.486 2012 SEP 29 - 2016 NOV 27 56199 - 57719 6.483 2016 NOV 27 - 2016 DEC 27 57719 – 57749 6.486 2016 DEC 27 - 2017 JAN 31 57749 – 57784 6.489 2017 JAN 31 - 2017 FEB 25 57784 – 57809 6.492 2017 FEB 25 - 2017 MAR 27 57809 – 57839 6.495 As the time scales UTC and TAI differ by an integral number of seconds (see Tables 1 and 2), UTC is necessarily subjected to the same intentional frequency adjustment as TAI.