What's $2.5 million between friends?  For Lionsgate, it's the difference between their initial estimate for the debut of "The Hunger Games" and the actual figures that came in Monday morning.

Initially, Gary Ross' adaptation of Suzanne Collins' novel was expected to make a staggering $155 million in its first three days.  Instead, it actually grossed $152.5 million or $2.5 million less than the estimate.  Box office estimates are usually incredibly spot on, but discrepancies do occur and this is nothing that out of the ordinary.  Of course, some studios have been off up to $7 million when hyping up mammoth debuts (Paramount in particular has been guilty of this recently), but with the third largest three-day weekend opening of all time, no one is faulting Lionsgate for overestimating the Sunday gross. 

"Hunger Games" is still the third largest debut behind "Harry Potter and the Deathly Hallows, Pt. 2" and "The Dark Knight."   That's remarkable considering the film didn't benefit from higher 3D ticket prices (like "Harry Potter" did) and was a non-sequel (it is the only film in the top 10 at the moment that is not a sequel). Some other amazing marks Katniss and her friends hit over the weekend include:

- Top opening weekend ever in March or in the Spring season.

- Largest opening weekend for an independent studio (Lionsgate is considered an independent and not a member of the MPAA).

- It had the second largest Saturday single day gross ever: $50.3 million.  That's just behind "Spider-Man 3's" $51.3 million and "The Dark Knight's" $47.6 million.

- With $$117.5 million in the bank by end of day Saturday, "The Hunger Games" is the second fastest film to gross $100 million after "Harry Potter and the Deathly Hallows, Pt. 2" found $133.4 million.  "The Twilight Saga: New Moon" is third with $114.9 million in its first two days.

The big question now is where will "The Hunger Games" end up on the all-time list? Typically, a film fueled by teenage audiences has a short shelf life at the local multiplex, but with an A Cinemascore grade from audiences and strong reviews, "Hunger Games" may expand its base with adult moviegoers who typically venture to the theaters after crowded opening weekends. However, Lionsgate is no doubt looking for at least $325 million domestic gross when all is said and done.

Upcoming releases this weekend include "Wrath of the Titans" and "Mirror Mirror."  Neither is expected to top "Hunger Games" in its second frame.