The search engines are overwhelmed with pages, and older pages are being dropped from the search engines, by putting the date it become irrelevant.
Sun, 8 May 2011 14:44:57
Search engines will put pages in supplemental.
Search engines will not index pages.
Search engines will not allow pages to show in search index.
By placing the date and year inside a page, we instantly create a way that could make the page irrelevant.
Do not put dates or year inside a page.