DALLAS (AP) ¿ MetroPCS Communications Inc. shares fell Thursday after the low-cost wireless provider reported a higher quarterly profit but cut its full-year subscriber forecast, citing continued economic weakness in the U.S. and increasing wireless market competition.

Shares of MetroPCS fell 69 cents, or 10.4 percent, to $5.93. Earlier, the shares traded as low as $5.65, its cheapest level since MetroPCS began trading publicly in April 2007.

MetroPCS said it earned $73.6 million, or 21 cents per share, for the third quarter ended Sept. 30. That's an increase of 64 percent from $44.9 million, or 13 cents per share, in the year-ago quarter.

Revenue rose 30 percent to $895.6 million. Service revenue, which makes up the majority of revenue, rose 33 percent to $812.3 million.

Analysts polled by Thomson Reuters expected a profit of 9 cents per share on $869.4 million in revenue.

MetroPCS had more than 6.3 million subscribers at the end of the quarter, compared with 4.8 million in the year-ago quarter. The company said this was below expectations and was caused by a drop in gross additions and increase in the rate of "churn," or customer turnover.

"We believe this was the result of continued U.S. macroeconomic weakness, an increasingly competitive environment, and upward adjustments we made to the price of certain handsets," said CEO Roger D. Linquist in a statement.

Average revenue per user rose 35 cents year over year in the third quarter to $41.08. The company attributed the gain to its different calling plans and a new unlimited international calling plan it rolled out in June.

The company also said that it now expects 1 million to 1.2 million in net subscriber additions for the full year, down from the 1.4 million to 1.7 million it had predicted previously.

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