I am trying to do some VAR analysis, but I can't get the tsset correct, because of how the data in the date is structured. The data is integers, not strings. But I can't tsset for quarterly without it saying there are gaps, but there are no gaps. As a work around I tried to generate two variables for the year and the quarter, but thats where I'm stuck. The data is in integers, but is currently displayed like:

DATE
Jan 1, 1972
Apr 1, 1972
Jul 1, 1972
Oct 1, 1972
Jan 1, 1973

I attached the file.