Mobile continues to be the digital download medium of choice in Japan, according to data released by local labels body the Recording Industry Assn. of Japan.

Mobile-based music downloads totaled 344.1 million in calendar 2006, up 33%, for a wholesale value of ¥48.2 billion ($398.2 million), an increase of 49%.

The RIAJ defines this category as comprising sales over wireless networks of full single tracks, ring tones, master ring tones and other related content, regardless of whether those sales were made on a per-track basis or by subscription.

PC-based music download sales by the RIAJ's 43 member companies, meanwhile, totaled 23 million last year, for a wholesale value of ¥5 billion ($41.3 million), an increase of 172%.

The RIAJ defines the category as comprising singles, albums, mini-albums and "other related content" sold over wired networks, with albums and mini-albums counting as single units regardless of the number of tracks they contain.

The association says that although the data doesn't differentiate between sales of single tracks and albums, singles account for the overwhelming majority of download sales.

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