>How about using a date field + an integer field? The date field would have the current correct day and month and the integer would have the number of years to offset that date. I expect it would make your calculations a bit more complex, though.

So, basically, if I would have the following values presently in one date time field (the time is not indicated):

23/06/1986
03/01/1753
01/01/1400
02/02/2006
05/06/1516
06/07/1517

I would be able to use something like this spreaded in a date time field (time still not indicated) plus an integer field:

23/06/2006 20
03/01/2006 253
01/01/2006 606
02/02/2006 0
05/06/2006 490
06/07/2006 489

Is that how you saw it?