max of date

[Vijay77]

Hi,

   i have two date variables asdtc and estdtc i want to get max(estdtc) when estdtc<=astdtc by subect ? any help would be appreciated

i have tried following

proc sql;

CASE WHEN substr(ESTDTC,1,10)<=ASTDTC THEN MAX(ESTDTC) group by subbjid; quit;

but it giving values of max(estdtc) by subject not based on estdtc<=astdtc

subjid                                     estdtc          astdtc

2008                       2019-03-31T06:50   2019-04-02
2008                      2019-03-28T19:02    2019-04-02
2008                     2019-03-27T19:34    2019-04-02

[PeterClemmensen]

Can you post some sample of your data? Makes it much easier to provide a usable code answer.