elapsed time

Hello everyone.
 I am trying to print a basic timing on how long does a particular program
takes to do its stuff.
Since the program runs for several minutes, I am not concerned in anything
more precise than seconds.
 I did the following:

DBENCH S T
DBENCHSECS S 4 0
/FREE
BENCH = %TIME;
// a whole lot of program
// many reads, calculations and writes

BENCHSECS = %DIFF(BENCH:%TIME:*SECONDS);
write ENDOFREPORT;
*INLR = *ON;

//END-FREE
*ENDOFREPORT* includes the *BENCHSECS* field. And the problem is that it
keeps coming as zero.
It's probably something quite idiotic, as the results of %TIME not being the
kind of results that I think I want.
 Any ideas?
 Thanks again, regards.
 I.-