how to add rows in sas

[novinosrin]

HI @annypanny   Here is a very simple solution that should be easy to follow for most. I have also written comments where necessary to help you understand the flow of the logic. I hope this is convenient enough.

data have;
input Sc_no $ perf date :ddmmyy10.;
format date ddmmyy10.;
datalines;
A000855A  -0.28305 30112018
A000855A  0.49306 30092018
A000855A  2.14955 31032019
A000855A  2.53133 31072018
A000855A  4.19303 31012019
A000856A  -0.28305 30112018
A000856A  0.49306 30092018
A000856A  2.14955 31032019
A000856A  2.53133 31072018
A000856A  4.19303 31012019
;
/*Get the current month date and start date backtracking 61 months*/
%let  curr_dt=%sysfunc(intnx(mon,%sysfunc(today()),0,e));
%let  start_dt=%sysfunc(intnx(mon,&curr_dt,-61,e));
%put &=curr_dt;
%put &=start_dt;

/*Create the backtracked monthend date list*/
data backtracked_dates;
 date=&start_dt;
 do while(date<=&curr_dt);
  output;
  date=intnx('mon',date,1,'e');
 end;
 format date ddmmyy10.;
run;
/*Combine the dates with distinct Sc_no*/
/*This will give you a complete date list associated with each scn_no */
proc sql;
create table combine_scno_dates as
select *
from 
(select distinct Sc_no from have), backtracked_dates
order by Sc_no,date;
quit;
 
/*Now, Join the combine_scno_dates back with have to get the needed result*/
proc sql;
create table want as
select a.*,case when perf=. then 0 else perf end as perf
from combine_scno_dates a left join have b
on a.Sc_no=b.Sc_no and a.date=b.date
order by a.sc_no,a.date;
quit;
/*Print and check the results*/
proc print noobs;run;