February 24, 2013
His Age was 41-7-5
I recently found this Windham NY gravestone listing:
Sylvanus G. Miller, d March 13, 1860 aged 41y7m5d
Using the calculator, we can assess that he was born Aug 8, 1818.
So, yes, he should be included in his family’s 1820 census.
Very helpful at times.
There are numerous online tools which will do that calculation for you such as the Tombstone Birthdate Calculator on Rootsweb. It looks like this: