Try Date::Manip.

use Date::Manip; 
$dyear = Delta_Format(DateCalc('1925-12-22 00:00UTC', '2012-03-22 00:0
+0UTC'), '%yys');
# $dyear is now 86.249, the difference between the two dates in years
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Time::Piece is a core module.

#!/perl
use strict;
use warnings;

use Time::Piece;

my $datt = Time::Piece->strptime("2012-03-22", "%Y-%m-%d");
my $datf = Time::Piece->strptime("1925-12-22", "%Y-%m-%d");

my $diff = $datt - $datf;
my $result = $diff->years;
print "$result years\n";
$result = $diff->days;
print "$result days\n";
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prints:

C:\Perl\bin>perl pm_1033486.pl
86.2496055700018 years
31502 days
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See also Time::Seconds for the data values transformation.

Yes. (Warning: Mathematician's answer. Correct but useless.)

So, if you're sure that there IS such a module (mathematicians cannot tell anything unproved?..), could you please tell me it's name?..

Date::Calc should do, see function N_Delta_YMD.

1925-12-22T00:00:00 - 2012-03-22T00:00:00 = 86 years and 3 months
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