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    Fwd: Another Nautical Almanac question (from Increments and Corrections thread)
    From: Stan K
    Date: 2013 Jul 17, 08:28 -0400
    Catherine Hohenkerk came through again.  There are actually four values that changed.  The only question is whether they changed in 2002 (or possibly 2001) according to the commercial editions I have, or in 2003 as she states (UK edition?).


    -----Original Message-----
    From: Hohenkerk Catherine <Catherine.Hohenkerk@UKHO.gov.uk>
    To: slk1000 <slk1000@aol.com>
    Sent: Wed, Jul 17, 2013 4:52 am
    Subject: RE: Another Nautical Almanac question

    Dear Stan,
    Increments and Corrections are fixed tables. 
    NA 2003 was the first NA that had these fixed tables generated by computer, rather than using copies of tables that had been generated many many years previously.
    If you compare the look of the Increment and Corrections tables of NA 2003 or a modern NA with NA 2002 or older versions you will see that the printing looks a lot different.
    I can confirm that the UK edition of NA 2002 has the old printed version of the tables.
    I have looked up my files and can confirm that the NA 2003 was the first year to include the modern tables.
    My notes also confirm that there were 4 cases where the rounding was different.  The two cases you mention and minute 52 with v/d 9.2 and 16.4.  The decision was taken to continue and use the modern values.
    You are the first person to notice this!
    I trust this answers your question.
    HM Nautical Almanac Office
    United Kingdom Hydrographic Office
    Admiralty Way
    Taunton TA1 2DN
    -----Original Message-----
    From: slk1000@aol.com [mailto:slk1000@aol.com]
    Sent: 16 July 2013 21:50
    To: Hohenkerk Catherine
    Cc: slk1000@aol.com
    Subject: Another Nautical Almanac question

    After years of having been taught, thinking, and teaching that the Increments and Corrections table at the back of the Nautical Almanac is the same year after year, I have discovered that this is not the case.  I have found at least two of the almost 22000 values in the table that changed between 2000 and 2002.  (This might have happened in 2001, but I do not have a 2001 Almanac.)  Specifically:

    m        v or d         Corr (2000)    Corr (2002)
    22        2.8                1.1                1.0
    22       16.4                6.2                6.1

    There may be others, but even though I have recently been laid off and have the time, I can't see spending it comparing Almanacs ;-)

    Can you tell me anything about this?

    Also, did this change occur in 2001 or 2002?

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