Maybe not the most efficient or compact, but here's a reliable DateTime solution. 
use DateTime::Format::ISO8601 qw( );

my $dt = DateTime::Format::ISO8601
    ->parse_datetime('1899-12-30')
    ->add( days => 40254 );

print($dt->ymd(), "\n");

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In reply to Re: Looking for an efficient way to do datetime transfer by ikegami
in thread Looking for an efficient way to do datetime transfer by lihao

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