I echo djp: Don't Reinvent the wheel. Date and time calculations (e.g. month changes, leap years, timezones) is surprisingly difficult to get right. Don't let that prevent you from doing the exercise though. 
$ perl -l
use strict;
use warnings;
use DateTime;
print DateTime->new( year => 2007, month => 9, day => 10)->subtract( d
+ays => 5 )->ymd();
__END__
2007-09-05

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--
Andreas

In reply to Re: Prior Date by andreas1234567
in thread Prior Date by Anonymous Monk

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