Analyst firm the NPD Group claims US peer-to-peer usage began to increase in October 2003, despite the Recording Industry Association of America (RIAA) continuing to litigate against persistent file sharers.

Russ Crupnick, vice president of The NPD Group said: "Recent information from complementary data services at NPD, however, noted an increase in the number of households and individual consumers using P2P services to download digital music files."

It seems the number of households downloading digital music files was up 14 per cent in November 2003 compared with September. This up-turn comes after six straight months of declines in digital file acquisition, since April 2003.

The analysts point out that the October-December quarter is one of the peak music buying periods and that consumers have more leisure-time in these months.