Sorry, I couldn't find pricing data for that day. The closing price for Microsoft (MSFT) on August 21, 2009 was $18.14. It was up 2% for the day. The latest price is $488.37.
DATE
OPEN
HIGH
LOW
CLOSE
VOLUME
August 21 2009
$17.79
$18.15
$17.67
$18.14
69,018,922
Daily pricing data for Microsoft dates back to 3/13/1986, and may be incomplete.