“In the latest quarter the iTunes top line grew by 32%,” Horace Dediu reports for Asymco.

“Quarterly revenues topped $4 billion (a new high) and the company suggests that this rate is maintainable by stating it has a ‘$16 billion annual run rate,'” Dediu reports. “The content portion of iTunes revenues was $2.4 billion, up from $2.1 billion sequentially. Growth into Q1 is not unusual as many holiday iTunes gift cards are redeemed during January.”

Dediu reports, “In March Apple reported that they have 500 million iTunes [users] so one way to think about the iTunes business is to say that iTunes users purchase content and services at the rate of about $40 per year.”

Much more – including the usual excellent charts, in the full article here.