How should the age field be indexed when it was recorded as 15/30 or 11/311?

Searle Marie1

I am reviewing US Mortality schedules. I have read and understand the instructions for indexing the age field by rounding down to the nearest age. The fraction 8/12 should be indexed as 0. I'm just curious to know if the above fractions indicate an age other than 0.

barbaragailsmith1

15/30 is 15 days (the 30 being days of the month) so would be indexed as 0. I don't know about the 11/311.