chilly charly -
All of the data was migrated into the new forums and the searches aren't limited to 90 days (unless you choose to limit them).
I went to the main page (forums.ni.com) and entered Principal Component Analysis and saw the answers from back in 2002 that I think you are looking for.
http://forums.ni.com/ni/board/message?board.id=170&message.id=36050
Hope that helps,
Molly K.
Web Support Manager
National Instruments
Molly K.
Web Support & Operations Manager
National Instruments