Updates to time/date variables were introduced in Stata 10.
Stata already had date variables; now it has time variables (and time-and-date variables, too). Time is recorded with up to millisecond resolution, which will be important for some. Also, Stata’s time variables will work with or without leap-second adjustment. You may never have heard about leap seconds, but there are clocks that are adjusted for them, and clocks that are not, and in computer-generated datasets, time stamps come both ways. Stata can work with either one.
You can now record values like 25jun2007, or 13:42:41.106, or 25jun2007 13:42:41.106.
Stata 10 has functions that make it easy to input date, time, and date-time variables, so you can read data recorded as June 25, 2007 1:42 p.m., or 6/25/07 13:42, or 250620071342106, or Mon Jun 25 13:42:41 CDT 2007.
Stata 10 has formats that let you display date, time, and date-time variables any way you want, including any of the above, and lots more.
To see more details, click here.