Fears that an impending American recession is eroding US corporate profits were heightened last night after Apple gave warning that sales for the last quarter of the year would be $500 million lower than expected.

On Wall Street, traders marked down the price of Apple stock by 10 per cent in after-hours trading as the maker of iPods and the iPhone published its outlook and third-quarter results after the New York stock market had closed. Apple shares fell to $149 after hours, having traded at $186 in May.

Wall Street largely ignored Apple’s better than expected 37 per cent surge in revenues for the third quarter to $7.46 billion (£3.7 billion), a performance that represented the technology company’s best quarterly period in its history, but the Silicon Valley company last night boasted that it had increased profits by 23 per cent to $1.07 billion for the three months to June 28.

Speaking on a conference call to investors last night, Peter Oppenheimer, the chief financial officer, said that Apple’s personal computer sales were growing at three times the rate of the rest of the market.

However, traders were unnerved by Apple’s slide in gross margins, from 36.9 per cent to 34.8 per cent, indicating that it is being forced to cut prices to cushion sales growth. The new iPhone 3G is currently being advertised as “Twice as Fast. Half the Price” and is expected to be sold for $199.

Apple, which launched the iPhone a year ago, sold 717,000 during the period. It allows users to access the internet, play music, make calls and store data in one device. In the same period last year, Apple sold 270,000 iPhones. At the same time, the group sold more than 11 million iPods, up 12 per cent from the year before.

While Apple’s third quarter performance was robust, Wall Street is anxiously looking for signs that Americans are cutting back on nonessential purchases as they struggle with the cost of fuel, surging food prices, reduced credit facilities and the housing slump.

Official statistics have shown that consumer confidence is at its lowest for 28 years. Wall Street, however, may draw some consolation that about two fifths of all Apple revenue is derived from outside the US.

Apple chose to dodge speculation about the health of its chief executive Steve Jobs, who unusually failed to attend the group’s conference call to discuss quarterly earnings. Investors have become increasingly worried about his health after he appeared at the company’s annual developers’ conference last month having lost a significant amount of weight.

In October 2003, he was diagnosed with pancreatic cancer and underwent surgery to remove a tumour.

Bite-sized

— 2,496,000 Macs sold (up 41 per cent)

— 11 million iPods sold (up 12 per cent)

— 717,000 iPhones sold (up from 270,000)

— Apple’s figures for units sold in third quarter of its year, against same period the year before

Times Recommends

• Bank slashes rates by 1% to historic low
• House prices fall at fastest pace in 25 years
• Dragons’ Den judge exits Woolworths bid race