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:
German submarine U-9 (1935)
Table title:
Ships attacked
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Date </th><th colspan=1 rowspan=1 > Name </th><th colspan=1 rowspan=1 > Nationality </th><th colspan=1 rowspan=1 > Tonnage </th><th colspan=1 rowspan=1 > Fate </th></tr>
<tr> <td colspan=1 rowspan=1 > 18 January 1940 </td><td colspan=1 rowspan=1 > Flandria </td><td colspan=1 rowspan=1 > Sweden </td><td class="highlighted"  colspan=1 rowspan=1 > 1,179 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 19 January 1940 </td><td colspan=1 rowspan=1 > Patria </td><td colspan=1 rowspan=1 > Sweden </td><td class="highlighted"  colspan=1 rowspan=1 > 1,188 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 11 February 1940 </td><td colspan=1 rowspan=1 > Linda </td><td colspan=1 rowspan=1 > Estonia </td><td class="highlighted"  colspan=1 rowspan=1 > 1,213 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 20 April 1940 </td><td colspan=1 rowspan=1 > ORP Błyskawica </td><td colspan=1 rowspan=1 > Polish Navy </td><td colspan=1 rowspan=1 > 1,975 </td><td colspan=1 rowspan=1 > torpedo misfired, ship survived </td></tr>
<tr> <td colspan=1 rowspan=1 > 4 May 1940 </td><td colspan=1 rowspan=1 > San Tiburcio </td><td colspan=1 rowspan=1 > United Kingdom </td><td class="highlighted"  colspan=1 rowspan=1 > 5,995 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk (mine) </td></tr>
<tr> <td colspan=1 rowspan=1 > 9 May 1940 </td><td colspan=1 rowspan=1 > Doris </td><td colspan=1 rowspan=1 > French Navy </td><td class="highlighted"  colspan=1 rowspan=1 > 552 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 11 May 1940 </td><td colspan=1 rowspan=1 > Tringa </td><td colspan=1 rowspan=1 > United Kingdom </td><td class="highlighted"  colspan=1 rowspan=1 > 1,930 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 11 May 1940 </td><td colspan=1 rowspan=1 > Viiu </td><td colspan=1 rowspan=1 > Estonia </td><td class="highlighted"  colspan=1 rowspan=1 > 1,908 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 23 May 1940 </td><td colspan=1 rowspan=1 > Sigurd Faulbaum </td><td colspan=1 rowspan=1 > Belgium </td><td class="highlighted"  colspan=1 rowspan=1 > 3,256 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=1 rowspan=1 > 11 May 1944 </td><td colspan=1 rowspan=1 > Shtorm </td><td colspan=1 rowspan=1 > Soviet Union </td><td class="highlighted"  colspan=1 rowspan=1 > 412 </td><td class="highlighted"  colspan=1 rowspan=1 > Damaged </td></tr>
</table>
Question:
How many total tons has U-9 sunk or damaged?
Answer:
U-9 sank eight ships totalling 17,221 gross register tons (GRT) and damaging 412 tons.