Okay. This should be better     proc sql; create table output_rolling as      Select a.account_number       ,        A.bal_date       ,         Max(b.balance) as max_bal       ,         Min(b.balance) as min_bal       ,         Mean(b.balance) as avg_bal     From HAVE as a     Left join HAVE as b     On a.account_number = b.account_number      And intnx('month',a.bal_date,-11,'s') <= b.bal_date <= a.bal_date     ; quit;   so you join the data to itself and select all the balance between the current (12th) month and the 11 previous, for that account.   note.... For the early period, the summary values will be based on an incomplete sample (1 month, then 2, 3,4, etc) until you have a full 12 months history for that account. It is easy to set up a simple count and reject any output that is based on less than 12 balances. Ask if you need help with that. ... View more

  I can do it in 2 using a macro assignment:   proc sql; select distinct salary into :top1 - :top3 from have order by salary desc ; quit; proc sql; select * from have where salary = &top3. ; quit; ... View more