Global sales of digital music have tripled in the first six months of the year, according to the International Federation of the Phonographic Industry.
Sales totalled £460m in the first half of this year, equivalent to six per cent of all music industry sales, compared to £129m in the same period last year.
But overall recorded music sales fell 1.9 per cent to £7.7bn in the first half of this year, compared with £7.8bn in the same period last year.
"This is good news, but don't get overexcited. It's a strong growth but from a small base, and we would be worried if it wasn't growing like this by now," said Mark Mulligan, research director at analyst firm Jupiter Research.
"But the big problem is that around 16 per cent of internet users still download illegally so, if they cannot be persuaded to change, there will still be a big problem for the industry in the future."
The digital sales figures comprise individual tracks online, music subscription service fees, sales of full-length tracks and clips of master recordings for mobile phones.
"The fact is that the CD is still king because the majority of people use downloads as a kind of top-up. Very few buyers have switched completely. I think the CD will be king for another five years," said Mulligan.
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