Display Stata date serial number

[Emil Alnor]

Hi all

I need to sum up some statistics for all observations which have a date of december-2021 or later. The command would look something like:

Sum var if date>=[stata serial number for 1/12/2021]

My question is if there is an easy way of displaying serial numbers for dates in Stata?

I know how to solve the problem doing:

gen dec = date("1/12/2021", "MDY")
tab dec

But I wonder if there would be a less tedious way?

[Andrew Musau]

The terminology "serial number" is nonstandard. Stata dates are referred to as SIF (Stata Internal Form) values. There are convenience functions for these, e.g., -td()-

help td()

di td(06jan2022)
assert  date("1/12/2021", "MDY") > td(10jan2022)

Res.:

. di td(06jan2022)
22651

.
. assert  date("1/12/2021", "MDY") > td(10jan2022)
assertion is false
r(9);

.

[Emil Alnor]

Thanks, Andrew!