The independent research and consulting provider Generator have published a report showing that Apple’s music business could more than double in the next 5 years.

For the year ending September 2002 music was only 2.6 of Apples total revenue but as of September last year music had grown to 40 percent of Apples revenue and its expected to grow further this year.

“Most people now understand that Apple’s music business is the main source of growth but what’s not widely appreciated is just how big the music business could become in the future. It’s a big worry for some people in the industry,” says Andrew Sheehy, vice president of research at Generator.

It is expected that iPods will continue to be the main source of growth with the iTunes Music Store contributing to 37 percent of total music revenues by 2010.