I have some code that exports daily to an excel report.  There is one piece of code that I want to only export on Mondays.  Here's what I have so far.
 
Data _NULL_ ;
if weekday(today())=1 then
call execute ('PROC EXPORT DATA=inv3
                OUTFILE= "J:\Performance.xlsx" 
                DBMS=excel REPLACE;
                sheet="Inventory";
                RUN;');
run;