Need advise with indexing in google

[lcp03o]

I remember in March 2004 my vbulletin forum had 11,000 pages indexed in google. Today it has 9,000. How comes google is droping pages?? Is there anyting I can do to increase the amount of pages in google??

[paulyy]

Not really a vBulletin question: http://www.google.com/webmasters