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:
SM UB-5
Table title:
Ships sunk or damaged
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 class="highlighted"  colspan=1 rowspan=1 > 15 April 1915 </td><td colspan=1 rowspan=1 > Ptarmigan </td><td class="highlighted"  colspan=1 rowspan=1 > United Kingdom </td><td colspan=1 rowspan=1 > 784 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 12 August 1915 </td><td colspan=1 rowspan=1 > Sunflower </td><td class="highlighted"  colspan=1 rowspan=1 > United Kingdom </td><td colspan=1 rowspan=1 > 60 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 13 August 1915 </td><td colspan=1 rowspan=1 > E.M.W. </td><td class="highlighted"  colspan=1 rowspan=1 > United Kingdom </td><td colspan=1 rowspan=1 > 47 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 13 August 1915 </td><td colspan=1 rowspan=1 > J.W.F.T. </td><td class="highlighted"  colspan=1 rowspan=1 > United Kingdom </td><td colspan=1 rowspan=1 > 60 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 14 August 1915 </td><td colspan=1 rowspan=1 > White City </td><td class="highlighted"  colspan=1 rowspan=1 > United Kingdom </td><td colspan=1 rowspan=1 > 45 </td><td class="highlighted"  colspan=1 rowspan=1 > Sunk </td></tr>
<tr> <td colspan=3 rowspan=1 > Total: </td><td class="highlighted"  colspan=1 rowspan=1 > 996 </td><td colspan=1 rowspan=1 >  </td></tr>
</table>
Question:
What was the total gross register tonnage of the British ships sunk in 1915?
Answer:
UB-5 in 1915 sank five British ships of 996 gross register tons.