Amazon.com Inc. (AMZN) is known as the world’s largest online retailer. The company announced that customers have already bought about 1 million Kindle e-book readers and tablets in each of the last three weeks. These are by far the most detailed sales numbers the company has chosen to release.

The Kindle Fire tablet, which is priced at $199, has been Amazon’s best selling product since it was introduced 11 weeks ago. Despite the fact that there are security problems associated with the tablet, the sales of the tablet have not slowed down.

The Kindle Fire that has a 7” display and runs on the Android OS, costs less than half the price of the Apple iPad.

“They have not talked about numbers at all, so it’s a big deal that they for some reason think they need to disclose metrics now,” said Brian Blair, an analyst at Wedge Partners Corp. in New York. “It’s a part of their strategy to show the strength of it against Apple — a way to say, ‘we’re a player, and we’re going to start letting you know.’”

Kindle Fire sales have risen each week for the past three weeks.

“Kindle Fire is the most successful product we’ve ever launched – it’s the bestselling product across all of Amazon for 11 straight weeks, we’ve already sold millions of units, and we’re building millions more to meet the high demand. In fact, demand is accelerating – Kindle Fire sales increased week over week for each of the past three weeks,” said Amazon Vice President Dave Limp in a statement.