Even if I sell 1 song at the iTunes Music Store, I get only 4.5 cents

Even if artists belonging to Sony Music sell one song by iTMS, they are also royalty (royalties)4.5 centsIt seems that they are claiming that they should receive 30 cents or so in fact.
Techdirt: What A Surprise: Musicians Claim Label Is Cheating Them Out Of iTunes Royalties
http://techdirt.com/articles/20060428/036245.shtml

If it is 4.5 cents, it is about 5 yen in Japanese yen. If it is 1 dollar (exactly 0.99 dollars), it is about 114 yen, so royalty of about 4%. It is certainly low. In the case of Japan, how much is it?