BONN, Germany ( TheStreet) -- Deutsche Telekom ( DT), the biggest telecommunications company in Europe, posted a fourth-quarter loss of 3 million euros ($4.04 million) on an impairment charge of 500 million euros related mostly to problems in Greece. A year earlier, the company's loss was 730 million euros on impairment charges related to job cuts. "After a bumpy start, we rounded 2009 off with good results," said CEO Rene Obermann, in a statement Thursday. "Cost discipline was key to getting through economically challenging times. However, we did not save at the expense of the future, but continued to invest heavily." Deutsche Telekom, which owns T-Mobile in the U.S., said fourth-quarter revenue rose slightly to 16.2 billion euros. T-Mobile USA posted a 1.6% revenue decline in 2009 to $21.5 billion, and a 4.5% drop in adjusted earnings before interest, taxes, depreciation and amortization to $5.9 billion. Customers rose by 1 million in 2009 to 33.8 million. T-Mobile said net additions in the fourth quarter were 371,000. -- Reported by Joseph Woelfel in New York. Follow TheStreet.com on Twitter and become a fan on Facebook.