Here is one way:

use strict;
use warnings;
use DateTime;

my $dt1 = DateTime->new
(
    year  => 2013,
    month =>    9,
    day   =>   29,
);
 
my $dt2 = DateTime->new
(
    year  => 2013,
    month =>    3,
    day   =>   29,
);
 
my $dt3 = DateTime->new
(
    year  => 2013,
    month =>    3,
    day   =>   30,
);

my $dur1 = $dt2->subtract_datetime($dt1);
printf "29/03/2013 to 29/09/2013: %s months\n", $dur1->months;

my $dur2 = $dt3->subtract_datetime($dt1);
printf "30/03/2013 to 29/09/2013: %s months\n", $dur2->months;

[download]

Output:

17:44 >perl 1919_SoPW.pl
29/03/2013 to 29/09/2013: 6 months
30/03/2013 to 29/09/2013: 5 months

17:44 >

[download]

Update: Please see the correction by haukex, below.

Hope that helps,

Athanasius <°(((>< contra mundum Iustus alius egestas vitae, eros Piratica,

In reply to Re: More accurate way to calculate Date difference by Athanasius
in thread More accurate way to calculate Date difference by Anonymous Monk

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