Just a note of caution about your data ...   Storing your SYSTEM_DATE as a character string will make life difficult down the road.  Unless your data ranges over a very limited set of dates, you won't be able to sort the data and put the observations in chronological order.  The problem occurs if the data ever crosses over more than one month.  SAS handles this by storing dates as numeric values, but you will need to study up on what SAS expects and how to get your data into that form.  If you must use character strings, use YMD order and the full set of digits possible, such as:   2018-08-01 (assuming that represents August 1, 2018) ... View more