(Credit:Ed Ou/AP Photo)

Apple Inc. (Nasdaq: AAPL) set a new record as the most valuable company in stock-market history, after its stock hit a new intra-day high today. Its stock passed the $664 mark on Monday, up over 2.4 percent.

The market value of Apple, which is its stock price multiplied by the number of outstanding shares, reached $622 billion in midday trading, beating out Microsoft (MSFT), the previous record-holder, which peaked on Dec. 30, 1999.

Analysts attributed increasing buzz around Apple's next iPhone, expected to be released this fall, a possible iPad mini and a Wall Street Journal report last Friday about the company's expanded plans for a set-top box, to the jump in the stock price.

The new record does not take inflation into account, though, so Microsoft was worth considerably more in its prime. In inflation-adjusted dollars, Microsoft's market cap was about $850 billion on Dec. 30, 1999, The Associated Press reported. Microsoft is now worth about $257 billion. Its stock was trading around $30.76 in mid-day trading, down 0.45 percent.

Apple has been the world's most valuable company since the end of 2011. It worth 53 percent more than Exxon Mobil Corp, the second most valuable company. Shares of Exxon were trading around $87.95 mid-day, down 0.51 percent, making it worth about $405 billion.