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:
Hong Kong Supplementary Character Set
Table title:
Version history
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Version </th><th colspan=1 rowspan=1 > Total characters </th><th colspan=1 rowspan=1 > Publish date </th></tr>
<tr> <td colspan=1 rowspan=1 > GCCS </td><td colspan=1 rowspan=1 > 3,049 </td><td colspan=1 rowspan=1 > 1995 </td></tr>
<tr> <td colspan=1 rowspan=1 > HKSCS-1999 </td><td colspan=1 rowspan=1 > 4,702 </td><td colspan=1 rowspan=1 > 09/1999 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > HKSCS-2001 </td><td class="highlighted"  colspan=1 rowspan=1 > 4,818 </td><td colspan=1 rowspan=1 > 12/2001 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > HKSCS-2004 </td><td class="highlighted"  colspan=1 rowspan=1 > 4,941 </td><td colspan=1 rowspan=1 > 05/2005 </td></tr>
<tr> <td colspan=1 rowspan=1 > HKSCS-2008 </td><td colspan=1 rowspan=1 > 5,009 </td><td colspan=1 rowspan=1 > 12/2009 </td></tr>
<tr> <td colspan=1 rowspan=1 > HKSCS-2016 </td><td colspan=1 rowspan=1 > 5,033 </td><td colspan=1 rowspan=1 > 05/2017 </td></tr>
</table>
Question:
What supplementary sets were released in 2001 and 2004?
Answer:
Hong Kong Supplementary Character Set's revisions were released in 2001 (adding 116 characters) and in 2004 (adding 123 characters), totalling 4,941 characters.