FB was down 13.2% in the last week (201.53 -> 174.95) for "no reason", so that probably explains the difference.
When I see multiple questions from lots of people asking 'why' X stock is performing better than the expectations or other stocks, it also means that there was at least 90% of people that were on the wrong side of the trade, with the remaining 10% laughing all the way to the bank.