Another way is to use Time::Local, it has the advantage of being a part of core perl and works well when the incoming data has a known date format. A simple example-

    use Time::Local;

    my ($month, $mday, $year) = split "/", "06/08/2002";
    my ($month2, $mday2,$year2) = split "/", "06/18/2002";
    my $time = timelocal(0,0,0,$mday,$month-1,$year);
    my $time2 = timelocal(0,0,0,$mday2,$month2-1,$year2);

    my $diff = abs(($time - $time2)/(60*60*24));

    print "diff = $diff\n";
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You need to remember that the months are base 0. I grabbed the abs() difference but maybe you want to know if the difference is negative...

--
my $chainsaw = 'Perl';