The number of US music fans downloading music online increased by 27 per cent between November 2003 and March 2004, research claims.

Pew Internet & American Life Project ran a survey among 1,371 Internet users to reach its estimates, which include users of file sharing networks (LimeWire, KaZaa) and legal services, such as iTunes Music Store. Downloaders rose from 18 million to 23 million in the period.

The researchers also found that 14 per cent of "online Americans" say they used to download files but don't now, with a third of that group saying this was in response to fear of legal action by the Recording Industry Association of America (RIAA).

"The retreat is particularly pronounced among male Internet users between the ages of 18-29, and those who have broadband connections at home," the researchers say.

The survey also deduced a five-million person reduction in the number of KaZaa users, but also saw a rise in the number of users exploiting similar but smaller services.

There's a positive message for legal music distribution services in this report, which says: "While online music services like iTunes are far from trumping the popularity of file-sharing networks, 17 per cent of current music downloaders say they are using these paid services. Overall, 7 per cent of Internet users say they have bought music at these new services at one time or another, including 3 per cent who currently use paid services."

Over 11 million Internet users visited legal online music stores in March.

"iTunes, which reached more than 2.3 million Americans in March, has added nearly a million unique visitors since October 2003," the report states.

Demographics describing the online music population are beginning to emerge, the report suggests. For example: men are 50 per cent more likely to have downloaded songs compared to women; 38 per cent of those aged 18-29 say they download songs.

US music downloaders are beginning to register concerns for copyright, the report reveals, adding that the number of downloaders is lower "than the rates we were tracking in the first half of 2003, when more than 50 per cent of 18-29 year olds downloaded songs"