Updated

Roughly 25 million Americans — or 18 percent of the U.S. online population — have illegally downloaded a full-length movie, a study released Wednesday asserts.

In a study of 2,600 Americans polled via telephone and online, Digital Life America, a unit of Solutions Research Group, found that 32 million Americans had downloaded a movie at some point in the past.

Of that number, 80 percent of those users — or 25.6 million Americans — exclusively used peer-to-peer file-sharing sites, the vast majority of which have typically been used for exchanging copyrighted files.

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The number of regular file-sharing users doubled between 2005 and 2006, the study found.

"It's all inclusive but as we note a few lines down, 80 percent of downloaders use only P2P," said Kaan Yigit, the director of the study, in an e-mail Wednesday night. "CinemaNow!, MovieLink, Amazon Unbox are minuscule at this point — iTunes accounts for the bulk of whatever legal downloads there is."

The study's authors didn't clarify whether "downloaded" implied illegal downloads or participation in legal services such as CinemaNow!

Some file-sharing sites, such as BitTorrent.org, have also signed deals with movie houses for legal distribution of licensed films.

The authors of the study did not respond to a request for clarification by post time.

The perspective is that users simply don't care, or believe, that the studios are being hurt by piracy, the self-funded study found.

The survey revealed that 78 percent of those surveyed found that physically stealing a DVD from a store was a serious offense, but only 40 percent believed copying the movie digital also merited a serious offense.

The study pointed out that those surveyed described an example of a "serious offense" as parking in a fire lane.

"There is a Robin Hood effect — most people perceive celebrities and studios to be rich already and as a result don't think of movie downloading as a big deal," Yigit said, in a statement. "The current crop of 'download to own' movie services and the new ones coming into the market will need to offer greater flexibility of use, selection and low prices to convert the current users to their services — otherwise file-sharing will continue to thrive."

The study also found that:

— A typical movie downloader is 29 years of age; 63 percent of all downloaders are male, and 37 percent are female.

— A downloader typically has 16 full-length movies stored on his PC.

— Of those surveyed, 56 percent watched a DVD on a PC at some point, while 29 percent watched a DVD on a PC in the last month. About 25 percent have watched a streaming TV show on their PC.

The study's authors estimated their error rates at plus or minus 2.4 percent.

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