Error when using last.type

[Phil_NZ]

Hi SAS community,

Thank you for your dedicated helps recently, I learn a lot from it, I will try my best to upgrade my skills better to help the others in the future. 

Now, I have the data as below:

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.

.

.

while Type is the column of different stocks (character variables), others are numeric variables (daily data from1/1/1987 to 31/12/2019).

From this dataset have, I want to get the data of p_us, up_us, nosh at the end of each year for each stock (distinct Type).

My code is as below:

data want ;
set have;
by Type year;
if last.year then 
    do;
p_us_=p_us;
vo_=vo;
nosh_=nosh;
    end;
else delete;
run;

And when summarising the results that I receive, I saw that the data for vo, trading_vol, amihud, vo_ ends up with 0 observation as the proc means indicates below:

proc means data=have;
title"have";
run;
proc means data=want;
title"want";
run;

I also check my logic in my code but cannot find out the reason why it ends up like that, can you please have a look and point me out what should be the possibilities of such a result?

Thanks in advance!

[Kurt_Bremser]

Your data step keeps only the very last observation of each year for a type. Looks like your variables are always missing on these last observations.