An estimated 70 percent of the nearly 11,000 silent films produced in the US have been lost, according to a landmark study from the Library of Congress. The study, authored by historian and archivist David Pierce, finds that just 14 percent of all American silent films exist today in their original and complete format, while another 11 percent survive in complete form but in foreign language versions or formats of lower quality.

The study was commissioned by the Library's National Film Preservation Board, as part of a campaign to provide a more accurate inventory of the films that survive, and to facilitate efforts to preserve them. It is hoped that the study will spur other organizations to collaborate on the preservation and repatriation of silent films; of the 3,300 surviving American works, 26 percent were found to be in foreign countries.

In a foreword to the study, James H. Billington, Librarian of Congress, described the study's findings as "alarming," saying that even under the best circumstances, a large percentage of American film history will be lost to future generations.

"future generations have already lost 75 percent of the creative record."

"Even if we could preserve all the silent-era films known to exist today in the US and in foreign film archives — something not yet accomplished — it is certain that we and future generations have already lost 75 percent of the creative record from the era that brought American movies to the pinnacle of world cinematic achievement in the twentieth century," Billington writes.

The report cites several factors that contributed to the loss of the films, including the low quality of the film stock used to shoot the movies — which rendered them susceptible to fire and other damage — and the tendency for studios to destroy or neglect old prints. Together with the report, the Library of Congress launched an online database of every silent film element that has survived, along with their locations across the globe.

"The silent cinema was not a primitive style of filmmaking, waiting for better technology to appear, but an alternative form of storytelling, with artistic triumphs equivalent to or greater than those of the sound films that followed," the study reads. "Few art forms emerged as quickly, came to an end as suddenly, or vanished more completely than the silent film."