Rock acts still dominate US chart

System of a Down at a signing last week in Burbank, California

Rock artists continue to dominate sales in America, with a rock act topping the album chart for the fifth week running.

System of a Down's Mezmerize - their first album in three years - entered the Billboard chart at number one after selling 453,000 copies.

The Dave Matthews Band, Nine Inch Nails and Bruce Springsteen have all debuted in the top spot this month in what many see as a triumph for veteran acts.

This contrasts with 2004 when hip-hop, R&B and pop acts reigned supreme.

"A lot of rock bands up there at once is pretty impressive," said Doug Broad, executive editor of Spin magazine.

"It might kind of speak to a trend of people getting back to that music."

But Geoff Mayfield, Billboard's director of charts, attributed the current situation to the industry's cyclical nature.

"Each of those music genres gets to take turns," he said. "Sometimes you're hot, sometimes you're not."