The size of the legitimate UK digital music industry has doubled in the first half of 2005.

On Monday the British Phonographic Industry (BPI) trade association revealed that downloads in the first half of this year are at “almost twice the level for the whole of 2004”.

”With the growth in legal downloads already outstripping the growth in illegal file sharing, this is more good news for an industry beginning to make headway against the unauthorised use of music on the internet,” the organisation said.

BPI chairman Peter Jamieson said: “The record industry has enthusiastically embraced the new legal download services since their emergence into the mainstream little more than a year ago, and now we’re beginning to reap the rewards.

“The battle against illegal filesharing will continue, but we are delighted to have hit this milestone so soon.”

And more old-fashioned musical formats are doing well, too. Far from declining, the 7in vinyl single remains in demand, with quarterly sales up by 87.3 percent on last year. Overall there has been a 52.4 percent improvement in single sales, including downloads.

Annual sales of 7in vinyl singles now approach 1.4 million units, making this the best 12 months for the format since 1998, according to data compiled by the BPI.

The best-selling 7in single in the year ended March 2005 was a limited edition reissue of Iron Maiden’s Number of the Beast. Elsewhere the format is dominated by a new generation of UK rock acts including the Libertines, Babyshambles, Kaiser Chiefs and Franz Ferdinand.

Jamieson said: “Despite the incredible growth in download sales, there is still a huge demand for the collectible physical formats - it would be wrong to write them off just yet. Record companies are committed to meeting consumer demand in whatever format people want their music.”

British music is enjoying increasing success in the US, with 75 UK albums topping the 100,000-sales mark in the US in 2004, compared with just 66 in 2003.

The news comes just weeks after Coldplay’s third album, X&Y, entered at number one with first-week sales of 739,000. This in turn followed hot on the heels of big-selling albums from Oasis and Gorillaz.

Coldplay’s third studio album was also the first British album to simultaneously top both the US and UK charts since the Beatles’ ‘1’ collection in 2000.

“We have not seen anything like it for a decade,” said Jamieson. “From Coldplay to Oasis, Dido to Gorillaz, Lostprophets to Franz Ferdinand, British music is on the march.

“Music is still one of the UK’s great exports. We are by far the biggest exporter of music outside the US. We export many times more music to the US than the rest of Europe put together.”

The UK albums market saw a modest decline of 1.7 percent in the second quarter of 2005, although compilations suffered a more troubling 14.2 percent downturn.