Datetime Functions

[PaulPrevedoros1]

I am trying to systematically display BCE data and I have discovered something strange. When perform a calculate field on a date field and enter a value of -500000 the result is 16/01/531. Zero is 30/12/1899

I didn't think that the time suite worked this way? 

[jcarlson]

The story behind 30-Dec-1899 as the "Zero Date" is a long one, but pretty well summarized here at Stack Overflow.

How is your data being stored? Other databases and programs have similarly long-established and sometimes-interesting stories behind their "Zero Date", like IBM SPSS's October 14, 1582, which never actually existed.

[PaulPrevedoros1]

its a file geodatabase, python does have a min of year 1 AD, I have got the slider to work, by using 1 day = 1 year with year on being 31/12/1899