Please read the following table in HTML format from a webpage and then answer the question in detail according to the table. Each table cell is defined by a <td> and a </td> tag. Each table row starts with a <tr> and ends with a </tr> tag. 'rowspan=m' and 'colspan=n' represents a cell spaning over 'm' rows and 'n' columns.

Webpage title:
List of best-selling manga
Table title:
At least 100 million copies
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Manga series </th><th colspan=1 rowspan=1 > Author(s) </th><th colspan=1 rowspan=1 > Publisher </th><th colspan=1 rowspan=1 > Demographic </th><th colspan=1 rowspan=1 > No. of collected volumes </th><th colspan=1 rowspan=1 > Serialized </th><th colspan=1 rowspan=1 > Approximate sales </th></tr>
<tr> <td colspan=1 rowspan=1 > One Piece </td><td colspan=1 rowspan=1 > Eiichiro Oda </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 92 </td><td colspan=1 rowspan=1 > 1997–present </td><td colspan=1 rowspan=1 > 457 million† </td></tr>
<tr> <td colspan=1 rowspan=1 > Dragon Ball </td><td colspan=1 rowspan=1 > Akira Toriyama </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 42 </td><td colspan=1 rowspan=1 > 1984–1995 </td><td colspan=1 rowspan=1 > 250–300 million+ </td></tr>
<tr> <td colspan=1 rowspan=1 > Naruto </td><td colspan=1 rowspan=1 > Masashi Kishimoto </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 72 </td><td colspan=1 rowspan=1 > 1999–2014 </td><td colspan=1 rowspan=1 > 235 million† </td></tr>
<tr> <td colspan=1 rowspan=1 > Case Closed </td><td colspan=1 rowspan=1 > Gosho Aoyama </td><td colspan=1 rowspan=1 > Shogakukan </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 96 </td><td colspan=1 rowspan=1 > 1994–present </td><td colspan=1 rowspan=1 > 230 million† </td></tr>
<tr> <td colspan=1 rowspan=1 > Golgo 13 </td><td colspan=1 rowspan=1 > Takao Saito </td><td colspan=1 rowspan=1 > Shogakukan </td><td colspan=1 rowspan=1 > Seinen </td><td colspan=1 rowspan=1 > 191 </td><td colspan=1 rowspan=1 > 1968–present </td><td colspan=1 rowspan=1 > 200 million† </td></tr>
<tr> <td colspan=1 rowspan=1 > Black Jack </td><td colspan=1 rowspan=1 > Osamu Tezuka </td><td colspan=1 rowspan=1 > Akita Shoten </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 25 </td><td colspan=1 rowspan=1 > 1973–1983 </td><td colspan=1 rowspan=1 > 176 million </td></tr>
<tr> <td colspan=1 rowspan=1 > KochiKame </td><td colspan=1 rowspan=1 > Osamu Akimoto </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 200 </td><td colspan=1 rowspan=1 > 1976–2016 </td><td colspan=1 rowspan=1 > 157 million </td></tr>
<tr> <td colspan=1 rowspan=1 > Oishinbo </td><td colspan=1 rowspan=1 > Tetsu Kariya, Akira Hanasaki </td><td colspan=1 rowspan=1 > Shogakukan </td><td colspan=1 rowspan=1 > Seinen </td><td colspan=1 rowspan=1 > 111 </td><td colspan=1 rowspan=1 > 1983–2014 (on hiatus) </td><td colspan=1 rowspan=1 > 130 million </td></tr>
<tr> <td colspan=1 rowspan=1 > Slam Dunk </td><td colspan=1 rowspan=1 > Takehiko Inoue </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 31 </td><td colspan=1 rowspan=1 > 1990–1996 </td><td colspan=1 rowspan=1 > 126 million </td></tr>
<tr> <td colspan=1 rowspan=1 > Bleach </td><td colspan=1 rowspan=1 > Tite Kubo </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 74 </td><td colspan=1 rowspan=1 > 2001–2016 </td><td colspan=1 rowspan=1 > 120 million† </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Astro Boy </td><td colspan=1 rowspan=1 > Osamu Tezuka </td><td colspan=1 rowspan=1 > Kobunsha </td><td colspan=1 rowspan=1 > Shōnen </td><td class="highlighted"  colspan=1 rowspan=1 > 23 </td><td colspan=1 rowspan=1 > 1952–1968 </td><td class="highlighted"  colspan=1 rowspan=1 > 100 million </td></tr>
<tr> <td colspan=1 rowspan=1 > Doraemon </td><td colspan=1 rowspan=1 > Fujiko Fujio </td><td colspan=1 rowspan=1 > Shogakukan </td><td colspan=1 rowspan=1 > Children </td><td colspan=1 rowspan=1 > 45 </td><td colspan=1 rowspan=1 > 1969–1996 </td><td colspan=1 rowspan=1 > 100 million </td></tr>
<tr> <td colspan=1 rowspan=1 > Fist of the North Star </td><td colspan=1 rowspan=1 > Buronson, Tetsuo Hara </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 27 </td><td colspan=1 rowspan=1 > 1983–1988 </td><td colspan=1 rowspan=1 > 100 million </td></tr>
<tr> <td colspan=1 rowspan=1 > JoJo's Bizarre Adventure </td><td colspan=1 rowspan=1 > Hirohiko Araki </td><td colspan=1 rowspan=1 > Shueisha </td><td colspan=1 rowspan=1 > Shōnen/Seinen </td><td colspan=1 rowspan=1 > 124 </td><td colspan=1 rowspan=1 > 1987–present </td><td colspan=1 rowspan=1 > 100 million† </td></tr>
<tr> <td colspan=1 rowspan=1 > Touch </td><td colspan=1 rowspan=1 > Mitsuru Adachi </td><td colspan=1 rowspan=1 > Shogakukan </td><td colspan=1 rowspan=1 > Shōnen </td><td colspan=1 rowspan=1 > 26 </td><td colspan=1 rowspan=1 > 1981–1986 </td><td colspan=1 rowspan=1 > 100 million </td></tr>
</table>
Question:
How many copies of the volumes of Astro Boy were sold?
Answer:
The combined 23 volumes of Astro Boy have sold 100 million copies, making it one of the best-selling manga series of all time.