The release of Mac OS X Lion has helped Apple grow its share of the PC install base to nearly 13.5% in the U.S. and more than 6% worldwide, according to new statistics.

The latest tracking data from NetMarketShare shows Mac OS X has been steadily climbing the global charts, seeing its share rise from 5.60% in May to 5.67% and 5.96%, in June and July, respectively. By the end of last month, it had reached 6.03% worldwide and 13.42% in the United States.

Meanwhile, combined versions of Microsoft Windows continued to lead the worldwide market with a 92.90% share at the end of August, as Linux made its way into third place with a 1.07% share.

Mac OS X 10.7 Lion, Appleâs latest desktop operating system that started selling on July 20, already accounts for 1.03% share of the overall market compared to 1.17% for Leopard and 3.46% for Snow Leopard. Those figures are based on a sample of 160 million internet visitors that Net Applications says it tracks. While Leopard and Snow Leopard's marketshare dropped from 1.24% and 4% as users upgraded to Lion, Mac OS X's combined share still rose from 5.96% on the sale of new Mac models.



Desktop operating system market share by platform, August 2011

Lion adoption has significantly improved when compared with the Snow Leopard upgrade, Appleâs previous major Mac OS release. The latter claimed just 0.78% share after its first month and passed 1% only during its second month of sales, despite being priced, like Lion, at $29.99.



Desktop operating system market share by version, August 2011

The phenomenon may be explained by the new distribution system that Apple implemented for Lion. The operating system has been sold exclusively through the Mac App Store, a move that may have convinced more customers to upgrade earlier, as compared to Snow Leopard, whose default distribution method was via physical DVDs.

Apple began selling $69 Mac OS X Lion USB Thumb Drives earlier this month to accommodate the needs of customers that donât want to purchase the operating system straight from the digital store or download the large 3.49GB installation file over the Internet.



Mac OS market share worldwide