The box office saw one of the slowest weekends in years as "Chappie" flopped at No. 1 and "Unfinished Business" failed to pull in crowds.

The Sony release directed by Neill Blomkamp made a disappointing $13.3 million in 3,201 theaters and proved once again that science fiction films are hard sells. "Chappie's" opening was below expectations as Sony expected that it would open with $20 million. However, bad reviews and a lack of enthusiasm hurt the final total. The opening is the weakest for a Blomkamp film, whose first film, "District 9," was a huge surprise at the box office and whose second film, "Elysium," under performed. It was also the second consecutive sci-fi film to flop. Back in February, "Jupiter Ascending" failed to capture audiences as it million opened with $18 million and eventually made $45 million. The Sony film is likely to lose audiences next weekend when "Cinderella" and "Run all Night" open.

In second place, "Focus" was off 46 percent and made $10 million. To date, the feature has made $34 million, which is disappointing for a Will Smith film. The $50 million production is now on track to end its run with $50 million, but could finish below that.

In third place, "The Second Best Exotic Marigold Hotel" made a robust $8.6 million in its opening weekend. Playing in 1,573 theaters, the feature was on par with the original 2012 comedy, which also made $8.3 million, when it expanded nationwide. Fox Searchlight hopes to see the same success it had with the 2012 installment and with very few films targeted for adult audiences, this film could be the Indie breakout hit of the spring.

"The Kingsman: The Secret Service" continued to show a strong performance as it made $8.3 million in its fourth weekend. The feature has already made $95 million and will likely make the $100 million by the end of next week.

"The SpongeBob Movie: Sponge out of Water" added $7 million to its gross and brought its total $148 million. The feature should continue strongly with no family offerings currently at the box office.

"Fifty Shades of Grey" continued to lose audiences quickly as it made $5.6 million. Having already made $156 million, expect the movie to finish with at least $170 million.

Down 32 percent, "McFarland, USA" brought in $5.3 million. The Disney flick has already made a strong $29 million.

Meanwhile, Lionsgate's "The DUFF" has also continued to surprise. The well-received high school comedy made $4.8 million and brought its total to $26 million.

Vince Vaughn's "Unfinished Business" opened at No. 10 and made $4.8 million. The Fox release failed to gain the attention of audiences and it became the worst opening for a Vaughn film opening in wide release since 1998's "Return to Paradise." Throughout the past years, Vaughn's star power has waned. "Unfinished Business" marks his fourth consecutive flop, and with bad reviews and weak word-of-mouth, this comedy should easily leave theaters quickly.

A number of Oscar winners continued to do favorable at the box office. "American Sniper" became the highest grossing film of 2014 as it made an estimated $4.5 million and brought its total to $337 million. The feature, which won a Best Sound Oscar, is slated to end its run with $350 million.

The Julianne Moore starrer "Still Alice" added $1.6 million. The Oscar-winning film has already made $14.7 million and could easily end its run with $20 million.

"The Imitation Game" made an estimated $1.1 million. With $88 million, expect the Benedict Cumberbatch starrer to end its run with $95 million.

The Best Picture winner "Birdman" slowed down and made $733,000. The film has already made $41 million and could easily end its run with $45 million. However, the film is already on DVD and on demand, which limits it theatrical grosses.

Argentina's "Wild Tales" expanded in 28 theaters and made $145,000, bringing its total to $539,000. The Sony Pictures Classics foreign film is likely to cross the $1 million mark, making it a breakout hit.