This is fairly straightforward as long as you're not concerned with days of the month. Just roll your own code. 

# set numeric values
my $month = 
my $year = 
my $monthsback =

# subtract from current month
$month -= $monthsback;

# convert to proper range of values
if($month <= 0){$year--}
$year += int($month/12);
$month = $month%12;
if ($month == 0){$month = 12}

[download]

Well, maybe a little more straightforward if you were looking for future months. If you need to take days of the month into account, you would have to figure out how you want to deal with such thinge as Feb 31st.

In reply to Re: Month Dates by hangon
in thread Month Dates by Anonymous Monk

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.