Is there any way to compact the code so that it has fewer characters?

Use a hash. Or one of the date modules, like Date::Simple

use warnings;
use strict;
use Date::Simple qw(today);
print 'today     = ', today(), "\n";
print 'yesterday = ', today() - 1, "\n";

__END__

today     = 2013-08-02
yesterday = 2013-08-01
[download]