Once a year, Fortune releases its ranking of the top 500 global companies, and in recent years Apple has usually managed to nab a spot. This year, it rose to almost exactly the middle of the field at 253, up from 337 last year. The ratings are based on gross revenue, so it isn’t surprising to find larger PC manufacturers like Hewlett-Packard (32) and Dell (115) ranked significantly higher, despite the fact that Apple enjoys healthier profit margins.

Rankings are based on performance over the course of the last year, so the new list represents results for 2008. Apple first made the cut of the Global 500 list only two years ago for 2006, when they placed near the very bottom, at 492. Considering the short time frame, that’s actually a fairly impressive 2-year gain.

Take into account, though, that collective earnings for the list taken as a whole declined 85 percent this past year, which marks the most significant loss since Fortune began compiling it. Apple, Quanta, and HP were the only computer manufacturers on the list to post gains, with Apple outpacing all with a 38 percent boost in overall profits.

The results show that, if nothing else, Apple has been especially resistant to the effects of a down global economy thus far. Their success with the iPhone 3GS, coupled with the recent popularity of the newly upgraded 13-inch MacBook Pro, suggests that that resilience will continue through the summer and probably into the holiday season, especially if the rumored iMac price cuts come through as predicted.

The Fortune Global 500 is not to be confused with the Fortune 500, which only ranks American companies. When that list was released earlier this year in April, Apple had broken the top 100 for the first time since Steve Jobs’ return to the company in 1994. It reached number 71 on that list.

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