Memorial Day weekend a slow start for summer b.o.

A quieter Memorial Day Weekend capped an unusually sleepy summer kick-off month at the domestic B.O., as May revenues came in only slightly higher than totals for March.

Twentieth Century Fox’s “Avatar” carried over into 2010, earning $456.8 million during that period, while Disney’s March marvel “Alice in Wonderland” grossed $293.5 million during its first month of release. “Avatar” has cumed $749.1 million domestically; “Alice,” $333.2 million.

With a total of $190.5 million, four-day weekend numbers were the lowest since 2001.

Normally, box office returns are slow in the winter and spring months, building up to a summer blockbuster season that kicks off the first weekend in May.

But this year March was comparatively boffo, with $746.2 million. Last year, grosses for March came in at $580 million. May totals were $813 million both in 2010 and 2009. First quarter earnings in 2010 set the bar high, with 3D blockbusters “Avatar” and “Alice in Wonderland” propelling a sunnier-than-normal spring.

Over the last few years, studios pushed the summer launch weekend for major tentpoles and franchise offerings from Memorial Day up to the first weekend of May. But this year’s crop of franchise fare so far hasn’t yielded anything of the magnitude of “Alice” or “Avatar” and only one May title opened at over $100 million for the weekend.

Paramount’s comicbook sequel “Iron Man 2″ launched May 7 and earned $128.1 million for a cume of $279.7 million. Par and DreamWorks Animation’s 3D toon “Shrek Forever After” debuted with $70.8 million on May 21, and after topping the Memorial Day frame with $43.3 million, has cumed $146.8 million.

The holiday frame’s wide bows, Warner Bros. and New Line’s “Sex and the City 2″ and Disney’s “Prince of Persia: The Sands of Time,” opened under industry estimates with $36.8 million and $37.8 million, respectively.

Universal’s “Robin Hood” repped a considerable disappointment for the studio, given its $155 million budget, debuting with $36.1 million for a cume of $86.1 million.

Even the month’s top players, “Iron Man 2″ and “Shrek Forever After,” haven’t lived up to their franchise predecessors.

With middling results from several of Hollywood’s early summer offerings, some insiders suggest red-hot tracking for June’s slate could provide a B.O. boost.

Sony’s “Karate Kid” reboot bows alongside 20th Century Fox’s “The A-Team” on June 11, followed a week later by Disney’s 3D toon “Toy Story 3.” The latest toon installment enters fertile ground left by the first two offerings, which have cumed a collective $437.4 million.

Rounding out the month on June 25 are Fox’s “Knight and Day,” starring Tom Cruise and Cameron Diaz, and Sony’s “Grown Ups,” starring Adam Sandler and Kevin James.

Summit’s “Twilight: Eclipse” should perform boffo business on June 30.

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