Stata Date from a fraction year

#1
I have a DOB variable that has dates in the following format:

83.51
84.68
87. 51

The numbers before the decimal correspond to a year, for example 1983, 1984, 1987 and the numbers after the decimal is fraction of the year (1 year = 365.25 days). I need to convert these numbers to Stata dates and I am struggling. Can anyone please help? Thanks.