For one, markets were extremely overbought
For two, historically market reacted to the new Fed chair. Once Jerome Powell takes over as the new Fed Chairman on Feb 3, his stand on inflation & etc becomes known, market will be much less worried
For three, current yield curve, contradicted to 2000's, indicates 2018 should be a very good year.
For four, earnings, synchronizing globe growth, tax reform and etc
Though I am watching bonds very closely