Costco Wholesale Corp.'s net sales in December 2018 increased by 7.8% to $15.42 billion from $14.30 billion in December 2017.

For the five-week period ended Jan. 6, comparable sales of the warehouse club operator grew 6.1% year over year while e-commerce comparable sales were up 13.6%.

Costco's U.S. division recorded a 7.5% growth in comparable sales. In Canada, the company's comparable sales rose 2%, while other international markets grew 2.8%.

In November 2018, the company's net sales came in at $12.77 billion, up 9.8% compared to November 2017.