Derived date of birth

Question

For the dates of birth that are derived from grave marker inscriptions, what do we do if various online calculators give us different answers?  Do we just pick one and mark it uncertain?  Do we leave the day off and just go with month and year (unless the date crosses a month boundary)?

It seems the most common technique is to pick one and ignore the others.  Is this OK too?

Comments

I go by the documents.

Answer 1

Hi David,

If you don't have a birth, baptismal, or other contemporary source document that supports the birth date that you're entering, it should be marked as uncertain. If you have multiple sources that indicate conflicting dates, after evaluating the sources and making a decision, you can document what was decided and why in a Research Notes section of the profile.

Answer 2

One of the calculators is wrong.

Calculate it by hand, and determine which one is correct.

Probably the last time I did this was in elementary school. A long time ago!

In doing the subtraction, when “borrowing”, you need to remember that months have different numbers of days, and if one of the dates involves February, you may need to consider that the date is in a leap year, and use the right number of days.

Since this is a calculation that we do infrequently, if at all, there are videos that can refresh us in the technique. I had to look it up!

After all that, there is a presumption that the stated age in years-months-days is correct. Since it may not be, as Rick notes, mark the calculated date as uncertain.