Costco Wholesale Corporation reported sales results for the five weeks and 18 weeks ended January 5, 2020. The company reported net sales of $17.04 billion for the retail month of December, the five weeks ended January 5, 2020, an increase of 10.5% from $15.42 billion last year. Total comparable sales were 9.0%. For the 18 weeks ended January 5, 2020, the Company reported net sales of $56.99 billion, an increase of 7.5% from $52.99 billion during the similar period last year. Total comparable sales were 6.3%.