Summary Box: Deutsche Telekom reports Q4 loss

THE RESULTS: Telecommunications company Deutsche Telekom reports a loss of €1.34 billion ($1.77 billion) in the fourth quarter. That's more than double the losses from a year ago.

THE CULPRIT: Writeoffs for the fallen value of its U.S. and Greek businesses. Those writedowns more than wiped out a cash payment from AT&T because its deal to buy T-Mobile USA from Deutsche Telekom fell through.

IN THE U.S.: The U.S. business lost 800,000 customers in the fourth quarter and suffered from the launch of the new Apple iPhone model by three major national competitors in October.