Stocks Narrowly Mixed; Facebook Declines By: CNBC.com News May 22, 2012 at 09:51 AM EDT Stocks bobbed in and out of positive territory Tuesday as investors awaited data on existing home sales, but gains were limited after Fitch cut Japan's credit rating. Read More >> Related Stocks: Best Buy Facebook Google, Inc. Hewlett-Packard JPMorgan Chase & Co Take-Two Interactive