July 22 (Bloomberg) -- Apple Inc. fell 2.6 percent on the Nasdaq after its forecast for the back-to-school shopping season missed analysts' projections and questions resurfaced about Chief Executive Officer Steve Jobs's health.

Fourth-quarter profit will be $1 a share as sales climb to $7.8 billion, Cupertino, California-based Apple said yesterday. That compares with analysts' average estimates of $1.24 a share in profit and $8.3 billion in sales in a Bloomberg survey.

A slowing economy may make it harder for Apple to repeat its success in the quarter just ended, when it posted record sales of Macintosh computers and iPhones and better-than-expected demand for iPod media players. Back-to-school promotions and new product development also will curb profit margins, Apple said.

``The stock will be in a penalty box until you start to see the new products come out,'' said Chuck Jones, who helps manage $17 billion in assets, including Apple shares, at Atlantic Trust Private Wealth Management in San Francisco.

Analysts at Deutsche Bank, Morgan Stanley and Banc of America all cut their estimates on the stock. Apple dropped $4.27 to $162.02 at 4 p.m. New York time on the Nasdaq Stock Market.

Analysts raised questions about Jobs's health during a conference call yesterday. An appearance by the CEO in San Francisco last month sparked concern by attendees and bloggers that he may be ill. Jobs, 53, had successful surgery for a form of pancreatic cancer in August 2004.

``I think we're all concerned,'' RBC Capital Markets analyst Mike Abramsky told Bloomberg Television from Toronto today. ``Steve Jobs is so core to the soul and innovation of Apple.'' The analyst has an outperform rating on the shares.

`Private Matter'

``Steve loves Apple,'' Chief Financial Officer Peter Oppenheimer said on the call yesterday, responding to a question on Jobs's health. ``He serves as CEO at the pleasure of Apple's board. He has no plans to leave Apple. Steve's health is a private matter.''

Third-quarter net income climbed 31 percent to $1.07 billion, or $1.19 a share, a year earlier, Apple said in a statement. Sales rose 38 percent to $7.46 billion in the period, which ended June 28. That topped analysts' estimates of $1.08 a share in profit and $7.36 billion in revenue.

Apple sold a record 2.5 million Macs last quarter, wooing consumers and education buyers with models such as the ultra-slim Air notebook and the iMac desktop computer. The company also said it sold 11 million iPod media players and 717,000 iPhones.

Analysts' Estimates

On average, analysts were projecting sales of 10.3 million iPods, 2.2 million Macs and at least 700,000 iPhones, said Gene Munster at Piper Jaffray & Co. in Minneapolis.

Apple took the U.S. economy into account when devising its latest forecast, Oppenheimer said. The company's sales and profit projections have topped analysts' estimates for eight straight quarters. That prompted some investors to discount the forecast.

``I try not to read too much into that number because, typically and frankly, it's not often a good indication of where the quarter ends up,'' said Tony Ursillo, a Boston-based analyst at Loomis Sayles & Co., which owns Apple shares.

Apple, which introduced the original iPhone in June 2007, ran out of inventory in May as it prepared a new version of the wireless device. The company opted to delay recording sales from phones sold last quarter until it released a software upgrade.

New Model

That update accompanied the introduction of Apple's new iPhone 3G in 21 countries on July 11. The software, which also works with older iPhones, adds support for corporate e-mail and third-party programs. Since the new phone debuted after the quarter ended, it also wasn't included in yesterday's results.

Apple will recognize revenue from iPhones over 24 months, an accounting approach it adopted last year because of the way it updates the device with software, Oppenheimer said.

``The iPhone is a relatively small part of our total revenue and gross margin as a result of subscription accounting,'' he said.

Shoppers bought 1 million iPhones in the device's first three days, Jobs said. The company's 188 retail stores were mostly sold out after 10 days. And AT&T Inc., Apple's exclusive wireless provider in the U.S., said new buyers may have to wait as long as three weeks for an iPhone after nearly all of its 2,000 stores sold out.

As of last night, Apple had replenished stock at some of its stores, with 145 out of inventory, compared with 185 the day before.

``We are trying to catch the demand,'' Chief Operating Officer Timothy Cook told analysts yesterday on the conference call. Apple plans to deliver the iPhone to 20 additional countries by Aug. 22, he said, and a total of 70 markets later this year.

Gross Margin

Apple said its gross margin, the percentage of sales left after deducting production costs, will be 31.4 percent in the fourth quarter, down from the 34.2 percent it reported in the third quarter.

Oppenheimer said the back-to-school promotions and an unspecified ``future product transition'' will weigh on the profit margin, which will average 30 percent in fiscal 2009.

``We have some investments in front of us that I can't discuss with you today,'' he said yesterday. ``We're going to be delivering state-of-the art, new products that our competitors just aren't going to be able to match.''

To contact the reporter on this story: Connie Guglielmo in San Francisco at cguglielmo1@bloomberg.net

Last Updated: July 22, 2008 16:07 EDT