The Pirates of the Caribbean sequel has taken more than $400m

Ticket sales also rose by 6% to $3.85bn (�2bn) between May and August, tracking firm Exhibitor Relations has said.

In 2005 there was a drop of 11% in attendances, with revenue down 8%.

Meanwhile football film Invincible remains on top of the North American box office chart for a second week, according to studio estimates.

The movie, which stars Mark Wahlberg, kept recent releases Crank and The Wicker Man at number two and three respectively.

This year is it seemed like audiences found a picture they wanted to see every week, and sometimes two Jeff Blake, Sony Pictures

Crank features British actor Jason Statham as a professional killer, while The Wicker Man is a remake of the 1973 cult horror film, with Nicolas Cage in the lead role.

Definitive figures for the weekend box office - which includes a US public holiday - will be released on Tuesday.

Pirates of the Caribbean: Dead Man's Chest, starring Johnny Depp, accounted for more than 10% of the summer box office total, having taken more than $400m (�210m).

Studio executives said the results were good news compared to those of summer 2005.

Invincible sees Mark Wahlberg play a bartender turned footballer

"Last year, there was so much negative spin in the press and the minds of people, I think it created a mindset," said Chuck Viane, head of distribution at Disney, which released Pirates and animated comedy Cars.

"This year, everything started positive and it's continued straight through," he told the AP news agency.

Jeff Blake, vice-chairman of Sony Pictures, agreed: "The great thing this year is it seemed like audiences found a picture they wanted to see every week, and sometimes two."