Sorry, I couldn't find pricing data for that day. The closing price for the S&P 500 (GSPC) on December 30, 2011 was $1,257.60. It was down 0.4% for the day. The latest price is $5,971.61.
DATE
OPEN
HIGH
LOW
CLOSE
VOLUME
December 30 2011
$1,262.82
$1,264.12
$1,257.46
$1,257.60
2,271,850,000
Daily pricing data for the S&P 500 dates back to 12/30/1927, and may be incomplete.