Good afternoon, Thanks so much on your assistance on the following... I am using SAS 9.3 ( The Basic version... NOT Enterprise, etc.). I have a list of 500 people who each traveled to one city on a specific date (Visit) . What I would like to know is what is the range in days between the 1st and 2nd visit per city, then calculate the mean of these ranges ( based on cities with 2 or more visitis). What I did was sort the data by City & then by Visit (date variable). When I did this, found there is at least one visit per city. For some cities, there were only 2 visits, and for other cities there were > 2 visits. Figured out how to find range of first and last visit per city (in days) , and easily calculated mean by hand. (see code below)... proc tabulate data = a; class city; var visit; table city*visit, n nmiss (min max mean)*f=mmddyy10. range; run; But not sure how to calculate range per city based on 1st and 2nd visit only. Finding the mean of these ranges ( 2 or more visits) I can do by hand pretty quickly, but if possible to code easily, then I would love to know as well. I sincerely appreciate the help :-). Here is sample data City Visit Atlanta 22-Aug-15 Franklin 11-Nov-15 Licoln Heights 25-Oct-15 New Mexico 17-Sep-15 Palm Springs 04-Aug-15 Palm Springs 23-Aug-15 Palm Springs 09-Sep-15 Palm Springs 11-Oct-15 San Diego 21-Aug-15 San Diego 18-Sep-15 San Diego 29-Sep-15 Temecula 25-Sep-15 Thank you
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