Shares of Apple Inc. reached above $300 today, making it the second-most valuable company in the United States. This news comes as Apple prepares to release it’s forth-quarter earnings next week. The stock is up 43% so far this year.

Apple holds a market capitalization of $275 billion. It continues to be an innovated in the mobile computing market. Having sold over 3 million of its iPads since its debut in April, companies like Samsung, Acer and Hewlett-Packard have announced they will be releasing tablets based on Google’s Android operating system.

Apple has also hinted at updates to its operating system, OS X, that may be released before the end of the year. Although Apple computers were its beginning and still hold a strong portion of the market, the bulk of Apple’s worth comes from sales of iPods, iPhones and now iPads. Read more about Apple’s earning power at the Wall Street Journal.