Compare current month to previous month in a do loop macro

[Len18]

%MACRO DATA(beg, end, beg_1, end_1);
%LOCAL start start1 i j prvmth dt;
%let start=%sysfunc(inputn(&beg,yymmn6));
%let start1=%sysfunc(inputn(&beg_1,yymmn6));
%do i=0 %to %sysfunc(intck(month,&start,%sysfunc(inputn(&end,yymmn6))));
%do j=0 %to %sysfunc(intck(month,&start1,%sysfunc(inputn(&end_1,yymmn6))));
%let prvmth=%sysfunc(intnx(month,&start1,&j),yymmn6);
%let dt=%sysfunc(intnx(month,&start,&i),yymmn6);



PROC SQL;
	CREATE TABLE TEST_&DT AS 
		SELECT 
            PROD,
			CASE WHEN PROD IN (SELECT PROD FROM TEST2_&PRVMTH.)
				THEN 'OLD' 
				ELSE 'NEW' 
			END AS NEW 
		FROM IND_&DT							 
QUIT;

%END;
%END;
%MEND;


%let dt = %sysfunc( intnx( month, &todaysdate, -1, e), yymmn6. ); *TO CALC END OF 13MTH REPORTING PERIOD;
%put dt is &dt;

%let prevdt = %sysfunc( intnx( month, &todaysdate, -13, e), yymmn6. ); *TO CALC START OF 13MTH REPORTING PERIOD;
%put prevdt is &prevdt;

%let prvmth = %sysfunc( intnx( month, &todaysdate, -2, e), yymmn6. ); *TO CALC MTH PRIOR TO CURRENT MTH OF CURRENT YR;
%put prvmth is &prvmth;

%let prevyrmth = %sysfunc( intnx( month, &todaysdate, -14, e), yymmn6. ); *TO CALC MTH PRIOR TO START OF 13 MTH REPORTING;
%put prevyrmth is &prevyrmth;



%DATA(&PREVDT,&DT,&PREVYRMTH,&PRVMTH);

[Kurt_Bremser]

And what does the log from the macro say?

[Len18]

Actually, I just changed the name of the field created by the case when statement and that fixed it. Phew! Thanks!