Count duplicates in date order

[ChrisNZ]

Christina,
Your
[pre]ad1=admission1;[/pre] line is always executed, so the retained value is always over-written by the data set value.
Something like
[pre]if admission1 ne '' then ad1=admission1;[/pre] will ensure that the retained value is only overwritten if there is a valid value to use.

PS Your ID reads Christina, you sign Cristina. Are both interchangeable?

[DanielSantos]

Exactly.

You should assign the value of one variable to another, only if the first is not empty ('').

coalescec function is another way of doing the same.

See: http://support.sas.com/documentation/cdl/en/lrdict/61724/HTML/default/a002518268.htm

Cheers from Portugal.

Daniel Santos @ www.cgd.pt

[deleted_user]

Hi Daniel,

Thank you for your last response.
I have tried all weekend to use the retain and first/last statements in the correct way, but I am not succeeding...
I would really appreciate if you could help me a bit more with how to solve the problem.

Thank you very much!

:-) Christina