YRDIF function not working for some observations

[cris17]

Hi SAS communities,

I match merged 4 data sets into one. There should only be 1 observation per person, which includes the most recent visit. One data set had a Birth Date variable and another data set had a Visit Date variable. After merging all 4 I then had to create a new variable that shows what age the person was between Birth date and Visit Date. Below is my code and I think I did the code correctly, but in the log, it shows that 2 out of the 573 are missing data. I checked the data sets and they show both the Birth date and Visit date. It could possibly be the way I also made the 4 data sets, but want to know ifs a simple coding mistake. Below is my code and a screenshot of the partial log.

Let me know if you need more information

Thank you.

[PaigeMiller]

The log clearly shows that VisitDt is missing for these two observations.

it may be that when you merge these data sets, a missing VisitDt in one data set overwrites a non-missing VisitDt from another data set.

In the future, please post log as text (not screen capture) by pasting it into the window that appears when you click on the </> icon.