Sorry, I couldn't find pricing data for that day. The closing price for Microsoft (MSFT) on August 21, 2020 was $204.25. It was down 0.4% for the day. The latest price is $515.25.
DATE
OPEN
HIGH
LOW
CLOSE
VOLUME
August 21 2020
$205.05
$207.35
$204.09
$204.25
36,249,300
Daily pricing data for Microsoft dates back to 3/13/1986, and may be incomplete.