Sorry, I couldn't find pricing data for that day. The closing price for Costco Wholesale (COST) on December 29, 2017 was $167.44. It was down 0.2% for the day. The latest price is $1,064.04.
DATE
OPEN
HIGH
LOW
CLOSE
VOLUME
December 29 2017
$167.75
$168.77
$167.27
$167.44
2,028,358
Daily pricing data for Costco Wholesale dates back to 11/27/1985, and may be incomplete.