how to know that you have replicated obs

[Radwan]

Hello 

usually i use nodupkey option to eliminate the replicated observations, but i think this option removes all observations that occur next year and so on.

other words this option keeps only first year-observations while i have ten years observations, so  I need to know how much replicated obs i have in my datafile. 

thanks 

[PeterClemmensen]

You can use the DUPOUT= Option in the PROC SORT Statement.

[andreas_lds]

Please post the code you are using and an excerpt of the data and explain which obs are "accidentally" removed. The "nodupkey" option keeps only the first observation within a group defined by BY-statement.

[Radwan]

proc sort data=real_var1 nodupkey; by code year; run;

the observations were 34000 then became 1931 observations 

when i checked the number of firms it was 1931 firms.

while i have data for 9 years.

[andreas_lds]

You should add the year-variable to the by-statement, if you want obs for each year.

[Astounding]

Check your data.  It's probably messed up.  The result you describe would only be possible if the YEAR values were the same for all observations.  

[Radwan]

ok i will
thanks