How long are those Oscar coattails for box office indie films?

This year, the Academy Awards saw a 16 percent decline in viewership this year. Despite the fact that fewer people are watching the ceremony, the award itself is still one of Hollywood's most effective box office promotion tools, industry analysts say.

In fact, just about all of the major category winners saw a huge bump in sales from the prior week.

When the nominees for best picture were announced on January 15, the eight nominees—Sony Classics' "Whiplash," IFC's "Boyhood," Focus Features' "The Theory of Everything," Fox Searchlight's "Birdman," and "The Grand Budapest Hotel," Paramount Pictures' "Selma," Weinstein's "The Imitation Game" and Warner Brothers' "American Sniper"—had collectively earned about $207 million in domestic receipts.

Now, that sum has now skyrocketed by more than 200 percent to near $640 million, according to Box Office Mojo data.

"They get a free wave of promotion when the nominees are announced, and another wave after the ceremony," said Phil Contrino, chief analyst at BoxOffice.com. "If a film happens to be released in the sweet spot, which is somewhere in the middle of those two events, it can be a very valuable."

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Contrino said "American Sniper" was a great example of a perfectly timed theatrical release. It expanded in theaters a day after the nominations were announced and grossed $107.2 million over a three-day weekend.

Basking in the afterglow

Director Alejandro Gonzalez Inarritu, winner of Best Original Screenplay, Best Director, and Best Motion Picture for 'Birdman' attends the 87th Annual Academy Awards Governors Ball at Hollywood & Highland Center on February 22, 2015 in Hollywood, California.
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Director Alejandro Gonzalez Inarritu, winner of Best Original Screenplay, Best Director, and Best Motion Picture for 'Birdman' attends the 87th Annual Academy Awards Governors Ball at Hollywood & Highland Center on February 22, 2015 in Hollywood, California.

"Birdman," which took home the prize for best picture, saw a 119 percent increase in ticket sales during the weekend following the awards, raking in some $1.9 million. It earned about 43 percent of its total revenue after it was nominated.

In comparison, last year's winner, "12 Years a Slave," pulled in an additional $2.1 milliona 116 percent increase in weekend-to-weekend salesduring the weekend after the awards. The movie went on to make an additional $6.3 million, about 11 percent of its total revenue, after it won the award.

"Whiplash," was another standout at this year's awards, and got a boost after J.K. Simmons won in the best supporting actor category. The film's weekend receipts gained 19 percent week-over-week, marking its second-best performance of the awards season.

Sony's "Still Alice," whose star took home the prize for best actress, grossed another $2.6 million after the ceremony—with box office sales jumping 24 percent weekend-over-weekend. "The Theory of Everything," whose star won best actor, saw a 17.2 percent increase in weekend-to-weekend sales.

The only outlier was best animated feature winner "Big Hero 6," which saw a 3.7 percent decrease in ticket sales during the weekend after the Oscars.

Industry analysts note that post-award gross depends on a number of factors, including when the film was originally released and how soon it was available on demand.

"It's about timing. If a the nominations are announced close to when a movie is release, it will most likely see a bigger bump up in sales," Contrino said. "The timing wasn't as great as it was for past winners," he said, which include "Slumdog Millionaire," "The King's Speech," and "The Artist."

The aforementioned films went on to gross another $42.9 million, $21.1 million and $12.9 million, respectively, after winning best picture.

A much-needed revenue boost

Academy Awards: Did you know?
Academy Awards: Did you know?   

Awards shows are a subliminal message for people to go see a particular film, industry players say. When famous people come out to introduce a nominee, "that's a super great trailer being played in everyone's home across their TV screens," said Keith Simanton, managing editor of IMDB.

"The awards were invented to promote movies, and these are idiosyncratic films that could use the revenue boost," he said, speaking of the best picture nominees.

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The awards may have been created to promote sales, but according to a recent study, demand was reflected in the global black market, too. Oscar-nominated films saw a 385 percent spike in global piracy since the announcements were made on Jan. 15, according to Irdeto, an anti-piracy group.

The nominees weren't the biggest blockbusters of the year, but Simanton said he doesn't think that's necessarily a bad thing.

The Academy Awards may have started out as just a mechanism for promotion, but its "mandate has transformed over the years to find the best movies of the year, promote films and promote excellence...box office be dammed," Simanton said.

He said the categories would look a lot different if the Academy chased blockbusters with the intention to promote ratings of the telecast.

"If were going off of box office sales, then we'd have an entirely different landscape" of nominations, Simanton said, adding that the Academy would focus more on films like "Guardians of the Galaxy" and "Transformers" and less on "extremely independent films" such as "Whiplash" and "Boyhood."

Still, Hollywood watchers note that 2014's best picture nominees were the lowest grossers since 2010, when the Academy of Motion Picture Arts and Sciences expanded the category rules to include more nominees and allow more flexibility.

Tim Dirks of American Movie Classics' FlimSite.org, said the low gross wasn't surprising, since the Academy often nominates "serious films" to which the general population of moviegoers aren't drawn.

"There were a lot of other films that did really well at the box office, but they weren't what the Academy considers as respectable entertainment," Dirks said. The movie arbiters generally steers away from popular genres, including action adventures, family films and suspense thrillers.