Calculating days between two dates

[Jun Yoon]

I'm trying to calculate the duration between two dates?
My variables are like this

 
 DateBecame

This is a long type, format is %10.0g, and looks like the following

 
 19550101

So YMD format

My other variable

 
 DateLeft

Is also a long type, format %10.0g and looks like this

 
 19961001

Any help would be much appreciated!

Thanks in advance

[Joseph Coveney]

Try something like

generate int delta = date(string(DateLeft, "%10.0g"), "YMD") - date(string(DateBecame, "%10.0g"), "YMD")

[Nick Cox]

Cross-posted at http://stackoverflow.com/questions/4...wo-dates-stata

Please note our policy on cross-posting, which is that you should tell us about it. http://www.statalist.org/forums/help#crossposting

[Nick Cox]

Joseph gives very good advice, which I would extend: all date manipulations with these variables will be awkward unless and until you create daily date variables to work with. Thus I'd revise the advice to

gen SDateLeft = daily(string(DateLeft, "%10.0g"), "YMD")
gen SDateBecame = daily(string(DateBecame, "%10.0g"), "YMD")
format SDate* %td  
generate int delta = SDateLeft - SDateBecame

Now you have two Stata daily date variables that could be useful for other purposes.

Note that daily() is just the same function as date(), but I recommend using daily() as a more precise reminder of what it does.

[Jun Yoon]

Nick and Joseph,

That did the trick!!

I apologize about the cross-posting. I'll definitely make a note of that.

Thank you so much for helping out