Since its November 22 launch the Xbox 360 has been in short supply. Analysts, video game publishers and retailers have said shipments during the key holiday season fell short of expectations.

Microsoft said in a statement that its challenge has been to meet consumer demand for the Xbox 360. The company, which did not comment on the NPD numbers, said its manufacturing facilities are running at full capacity and that a third manufacturer will come online next month.

Microsoft last week confirmed its target of selling between 4.5 million and 5.5 million Xbox 360 consoles during the current business year, which ends June 30, 2006. It said in its statement on Friday that it will provide information on its Xbox 360 business during its quarterly financial report later this month.