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I have dates that are encoded in a MSSQL db but we need to crack the date encoding to build some software that can plug-in to the db(which belongs to us).

01/20/2011 = 76724

03/08/2011 = 76771

10/11/2011 = 76988

11/10/2011 = 77018

Any ideas on the encoding being used?

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improperly tagged? – user21436 Dec 22 '11 at 19:12
Looks to me like it's just the number of days since $76724$ days before 1/20/2011. Microsoft Excel can do the conversion pretty easily. – Qiaochu Yuan Dec 22 '11 at 19:13
Why did you think these dates were encoded? Encoded data should look random, not regular as this does. – lhf Dec 22 '11 at 19:22
up vote 5 down vote accepted

It seems to be the number of days since 28 December 1800.

Calculations checked with

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This appears to be the native date format of Clarion; see e.g. here or here. – Henning Makholm Dec 22 '11 at 19:37

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