Apple Computer Inc. (AAPL) shares jumped as much as 16 percent on Monday, to their highest level in more than 4 years, after a Wall Street analyst nearly doubled his price target on the stock.

Piper Jaffray analyst Gene Munster raised his 12-month price target to $100 from $52, citing a survey conducted by his firm showing that Apple's popular iPod (search) digital music players are helping boost sales of its signature Macintosh computers.

Another analyst, Robert Cihra, of Fulcrum Global Partners, also boosted his price target, although less dramatically, in a separate research note to clients. He set a new target of $65, up from $53.

The new price targets likely are spurring excitement in investors about the Cupertino, California-based company, said analyst Steve Lidberg of Pacific Crest Securities, who has a price target of $63 on the shares.

"One of the things that people are looking at, especially as they evaluate Apple going forward, is the growth of the iPod driving increasing adoption of the Mac system," he said.

Since the iPod's introduction in October 2001, Apple has sold more than 6 million of the devices. It now sells more iPods than it does its Macintosh desktop and notebook computers.

In a note to clients, Munster wrote that a Piper Jaffray survey of 200 iPod users in the United States found that 6 percent were formerly PC users who had bought a Macintosh computer after their purchase of an iPod.

Another 7 percent of those surveyed said they planned to buy a Macintosh, according to the survey.

Customer satisfaction with the digital music player also was very high, Munster said.

"We believe that the remarkable satisfaction with the iPod creates a word-of-mouth wildfire that generates new customer interest in Apple products," he wrote.

Munster has an "outperform" rating on the stock. He does not own any shares personally, and Piper Jaffray has no investment banking business with the company, he told Reuters.

Apple shares jumped $6.61, or 12 percent, to $61.78 in mid-morning trade on the Nasdaq stock market after rising as high as $64 earlier in the session.

Since the dot-come crash in 2000, Apple shares traded at little more than the value of the cash on its books, but have steadily climbed since April 2003.