Re: st: Time between 2 dates

[David Kantor <kantor.d@att.net>]

At 12:06 PM 1/26/2011, Laurie wrote:
> Hi all, i would like to calculate the time between 2 dates in a data set.
>
> I have start date like: 2010/08/02 meaning august 2nd 2010
> and end date like: 2011/02/08 meaming february 2nd 2011.
>
> I would like to know how many days are between the start date and 
> the end date.
> [...]

Presumably these values such as 2010/08/02 are of string types. First 
convert them to Stata dates. Assuming the variables are named 
startdate and enddate:
gen long startdate_n = date(startdate, "YMD")
gen long enddate_n = date(enddate, "YMD")

(The new variables are named with _n to signify "numeric", but of 
course, the names are arbitrary.)
You may also want...
format startdate_n enddate_n %d
(or any of several date formats) but that is optional.
Then just take the difference:
gen long daysbetween = enddate_n -startdate_n

HTH
--David

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