We have compiled the following long term charts that show points accumulated overnight (just ahead of) the Employment Situation report, then during the day session on the day of the report, and the combination of the two. 

 
Above is Feb 94 to Dec 09, and below is a zoom in of Sep 08 to Dec 09.

For 2009, Jul 09, Oct 09 and Nov 09 were negative gap days.  The day sessions were positive Aug 09 to Nov 09, but negative Dec 09.  What’s interesting in the longer term chart is that day sessions were positive in SPY throughout must of the late nineties bull run, but were not so during the subsequent bull run.  Perhaps that’s indicative of the jobless recovery.  SPY bottomed in Oct 02 on a higher low in the day session.  After that, there was a rally in day sessions, but then there was a resumption in the down trend until Oct 08, that lasted even during the bull market into Oct 07. 
 
Meanwhile, the gap stayed mostly flat and resumed its uptrend in early 2005.  Further, during the entire recent down leg, the worst drawdown in the gap was 2.34 SPY points, with most of the losses to SPY overall coming during the day session.  Accordingly, holding overnight ahead of the report (at least since mid-2003) appears to be more profitable than holding during the day.  It should be noted that there are outliers where SPY has gapped down ~1.50 points and it is not uncommon to have ~1.0 point gap downs, so caution should always be exercised when holding into the report.