By The Associated Press

(AP) - THROTTLING BACK 3-D: DirecTV cut back the programming hours on its 24-hour 3-D channel, n3D, due to a shortage of 3-D content. Programs were playing over and over. Now, the n3D logo will appear when nothing's available.

SLUGGISH START: Despite the popularity of 3-D movies, 3-D TV has not really taken off. Last August, AT&T Inc. said it was dropping ESPN 3-D from its U-verse lineup of video channels, citing low subscriber demand.

GROWING SALES: NPD Group says 3-D TV sales are growing in the U.S. They accounted for 11 percent of all flat-panel TV sales in the first three months of the year, nearly double the rate of a year ago.

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