Hi All,   I am a beginner in SAS. Can anyone please help me out on this.   1) As per my understanding FIRSTOBS will give the starting point for processing But in the below example, it is giving weird output. FIRSTOBS is working fine when I have used it with the SAS datasets. Please let me know how FIRSTOBS work in DATALINES. In the below example if I am decreasing the value of FIRSTOBS, output is changing in different manner. If I am mentioning FIRSTOBS=4 in the below example, it is throwing error i.e. FIRSTOBS option > number of observations in WORK.DEMO. Here no of observations is 6 which is greater than FIRSTOBS i.e.4 then why it is throwing error? Code:-  OPTIONS FIRSTOBS=3 ; DATA DEMO; INPUT PID AGE GEN$ NAME$; DATALINES; 1 23 M cdjdjdc 2 29 F kjkjvnvk 3 12 M vjbdkj 1 23 M vvl 1 23 M vnv 2 29 F vvkj ; RUN; PROC PRINT DATA=DEMO; RUN;   Result:- I have attached the output i.e. Output_1   2)MISSOVER in INFILE:- Will it replace only the last missing variable value with period sign ?   ... View more