Question: Does Summer Wars or Astro Boy use more American's as the voice actors?

Context paragraphs:
2009 in anime: At the Mainichi Film Awards, "Summer Wars" won the Animation Film Award and "Denshin-Bashira Elemi no Koi" won the Ōfuji Noburō Award.  "Summer Wars" also won the Japan Academy Prize for Animation of the Year.  Internationally, "The Sky Crawlers", "Summer Wars" and "First Squad" were nominated for the Asia Pacific Screen Award for Best Animated Feature Film.

Summer Wars: Summer Wars (Japanese: サマーウォーズ , Hepburn: Samā Wōzu ) is a 2009 Japanese animated science fiction film directed by Mamoru Hosoda, animated by Madhouse and distributed by Warner Bros.  Pictures.  The film's voice cast includes Ryunosuke Kamiki, Nanami Sakuraba, Mitsuki Tanimura, Sumiko Fuji and Ayumu Saitō.  The film tells the story of Kenji Koiso, a timid eleventh-grade math genius who is taken to Ueda by twelfth-grade student Natsuki Shinohara to celebrate her great-grandmother's 90th birthday.  However, he is falsely implicated in the hacking of a virtual world by a sadistic artificial intelligence named Love Machine.  Kenji must repair the damage done to it and find a way to stop the rogue computer program from causing any further damage.

Astro Boy: Omega Factor: Astro Boy: Omega Factor, released in Japan as Astro Boy: Tetsuwan Atom (アストロボーイ・鉄腕アトム ) , is a beat 'em up video game developed by Treasure and Hitmaker, and published by Sega.  The game was released for the Game Boy Advance on December 18, 2003 in Japan; August 18, 2004 in North America; and February 18, 2005 in Europe.  The game is based on Osamu Tezuka's manga and anime franchise "Astro Boy".  However, it also features characters and plotlines from the artist's entire canon of work.

The Original Astro Boy: The Original Astro Boy is a twenty-issue 1980s comic book series (with one Astro Boy short story in Speed Racer #17) by NOW Comics, based on the original Japanese "Mighty Atom" series by Osamu Tezuka.  The series was based mostly on the 1963 Astro Boy anime series, but begun to include elements from the 1980 series in later issues.  The comic went through three writers and artists, and embellished the original plotline, despite only covering the first episode of the 1963 series.

Osamu Tezuka's Star System: Over the course of his career, Osamu Tezuka reused the same characters in different roles in different stories.  The way that Tezuka used the characters in his "star system" can be seen as somewhat analogous to a film director frequently casting members of a regular "stable" of actors in different roles.  For instance, the "actor" "Shunsaku Ban" or "Shunsuke Ban", who played the detective in Osamu Tezuka's Metropolis, as well as played Astro Boy's teacher in Astro Boy.  Tezuka jokingly made a list of how much they were paid and based them on famous western actors in his time.

Astro Boy (film): Astro Boy is a 2009 Hong Kong-American computer-animated action-comedy superhero film loosely based on the manga series of the same name by the Japanese writer and illustrator Osamu Tezuka.  It was produced by Imagi Animation Studios, and directed by David Bowers, who co-wrote the screenplay with Timothy Harris.  Freddie Highmore provides the voice of Astro Boy in the film alongside the voices of Kristen Bell, Nathan Lane, Eugene Levy, Matt Lucas, Bill Nighy, Donald Sutherland, Charlize Theron and Nicolas Cage.

Astro Boy (character): Astro Boy (アトム , Atomu , lit.  "Atom") is a title character and the protagonist of the Astro Boy franchise.  Created by Osamu Tezuka, the character was introduced in the 1951 "Captain Atom" manga.  Astro Boy has appeared in animated television shows (notably the 1963, 1980, 2003 series) and feature film adaptations of its eponymous manga, as well as a live-action TV series, other works by Tezuka, and video games.

Astro Boy (1963 TV series): Astro Boy (Japanese: 鉄腕アトム , Hepburn: Tetsuwan Atomu , "Mighty Atom", lit.  "Iron Arm Atom") is a Japanese television series that premiered on Fuji TV on New Year's Day and is the first popular animated Japanese television series that embodied the aesthetic that later became familiar worldwide as "anime".  It originated as a manga of the same name in 1952 by Osamu Tezuka, revered in Japan as the "God of Manga."  After enjoying success both in Japan and abroad as the first anime to be broadcast overseas, "Astro Boy" was remade in the 1980s under the same name(s), and in 2003 as "Astro Boy: Mighty Atom".  It lasted for four seasons, with a total of 193 episodes, the final episode presented on New Year's Eve 1966.  At its height it was watched by 40% of the Japanese population who had access to a TV.  In 1964, there was a feature-length animated movie called "Mighty Atom, the Brave in Space" (鉄腕アトム 宇宙の勇者 , Tetsuwan Atomu: Uchū no yūsha ) released in Japan.  It was an anthology of three episodes; "The Robot Spaceship", "Last Day on Earth" and "Earth Defense Squadron".  The latter two were filmed in color.

Astro Boy (2003 TV series): Astro Boy (アストロボーイ・鉄腕アトム , Asutoro Bōi: Tetsuwan Atomu , lit.  "Astro Boy: Mighty Atom") is a remake of the 1960s anime series of the same name created by Osamu Tezuka, which was produced by his company, Tezuka Productions, Sony Pictures Entertainment Japan, Dentsu, and Fuji Television network.  It was also shown on Animax, who have broadcast the series across its respective networks worldwide, including Japan, Southeast Asia, South Asia, East Asia, and other regions.  It was created to celebrate the birth date of Atom/Astro Boy (as well as the 40th anniversary of the original TV series).  Under the original English name (instead of "Mighty Atom"), it kept the same classic art style as the original manga and anime, but was revisioned and modernized with more lush, high-quality, near-theatrical animation and visuals.  It combined the playfulness of the early anime with the darker, more serious and dramatic Science fiction themes of the manga and the 1980 series.  The anime broadcast in Japan on the same date as Atom's/Astro's birth in the manga (April 6, 2003) across Animax and Fuji Television.  It was directed by Kazuya Konaka and written by Chiaki J. Konaka at the beginning of the series.  Other writers included were Keiichi Hasegawa, Sadayuki Murai, Ai Ohta, Hirotoshi Kobayashi, Kenji Konuta, and Marc Handler, who was also executive story editor.

Professor Ochanomizu: Professor Ochanomizu (お茶の水博士 , Ochanomizu-hakase ) is an anime and manga character from the animated series "Astro Boy".  He is featured in all versions of Astro Boy to date, including the 1980s series, 2003 series, and the film.  Created by Osamu Tezuka, the character has since appeared in many of his other works.  He serves as a guardian to Astro, and sometimes also a caring family member.  He is also known in various English adaptations as Dr. Packadermus J. Elefun, Professor Peabody and Dr. O'Shay.

Supporting paragraphs: Summer Wars Astro Boy (film)
Answer: Astro Boy