Directional Bias For The Day: S&P Futures are lower; The odds are for a down day; watch for the break above 3670.50 for change of fortunes Key economic data report due during the day: PPI ( 0.1% vs. 0.1% est.; prev. 0.3%) at 8:30 AM Core PPI ( 0.1% vs. 0.2% est.; prev. 0.1%) at…