The National Assn. of Theater Owners reported Tuesday that the average ticket price in the first quarter of 2010 was $7.95, jumping 8% from $7.35 in the same period last year. That's the largest yearly increase since the association started tracking quarterly ticket price data in 2001.

The increase comes as consumer prices have risen mildly in the nation. During 2009, the consumer price index rose just 2.7% before seasonal adjustment, according to the U.S. Bureau of Labor Statistics.

The primary culprit at movie theaters is 3-D. The three highest-grossing movies in the first three months of 2010 -- "Avatar," "Alice in Wonderland," and "How to Train Your Dragon" -- have all generated the majority of their box office on screens that play the movie in digital 3-D and carry ticket price surcharges.

Although the theater owners association doesn't break out the average surcharge to see a movie on a digital 3-D screen, analyst Barton Crockett at Lazard Capital Markets recently estimated that it is now between $3 and $3.50. That includes the impact of large-format Imax 3-D screens that often cost $5 extra.

Prices are significantly higher in certain urban markets, including Los Angeles, where prices for 3-D movies are now as high as $19.50.

As a result of the rapidly rising prices, total box office revenue rose 8.6% in the first quarter, according to the theater owners association. However, not many more people went to movies. Attendance was up just 0.5%, with 334.9 million movie tickets sold in the U.S. and Canada.

"There's a really good chance that the average ticket price is going to continue to be significantly higher [than last year] based on 3-D attendance," said Patrick Corcoran, director of media and research for the theater owners association.

He noted, however, that the average ticket price is still lower than it was 40 years ago. Adjusted for inflation, going to the movies in 1969 cost $8.42, the association estimates.