According to survey firm Oricon, Nana Mizuki tops list on top-selling voice actresses and actors based on the sales of their vocal work.

With an overwhelming more than 1 billion yen of sales, Mizuki surpassed the sales of girl group Sphere, Yukari Tamura, Aki Toyosaki and Aya Hirano.

Mizuki is the voice actress to some notable anime characters such as Tsubasa Kazenari of Senki Zesshō Symphogear, Hyuga Hinata of Naruto and Ricotta Elmar of Dog Days.

Rankings

1. 1,192,900,000 yen Nana Mizuki
2. 422,300,000 yen Sphere
3. 173,100,000 yen Yukari Tamura
4. 148,000,000 yen Aki Toyosaki
5. 116,500,000 yen Aya Hirano
6. 102,300,000 yen Minori Chihara
7. 99,100,000 yen Mamoru Miyano
8. 96,400,000 yen Minami Kuribayashi
9. 93,500,000 yen Hiroshi Kamiya
10. 88,900,000 yen Megumi Hayashibara
11. 81,600,000 yen GRANRODEO
12. 79,300,000 yen Yui Horie
13. 69,800,000 yen Kenichi Suzumura
14. 66,700,000 yen Nao Tōyama
15. 63,000,000 yen Eri Kitamura
16. 62,600,000 yen Hiroshi Kamiya + Daisuke Ono
17. 60,200,000 yen Daisuke Ono
18. 40,100,000 yen Megumi Nakajima
19. 38,600,000 yen G.Addict
20. 36,200,000 yen Kanae Itō

The data covers from March 31, 2011 to April 1, 2012.

[Source]