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:
2005 Spanish European Constitution referendum
Table title:
Results
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Choice </th><th colspan=1 rowspan=1 > Votes </th><th colspan=1 rowspan=1 > % </th></tr>
<tr> <td colspan=1 rowspan=1 > For </td><td colspan=1 rowspan=1 > 11,057,563 </td><td class="highlighted"  colspan=1 rowspan=1 > 81.8 </td></tr>
<tr> <td colspan=1 rowspan=1 > Against </td><td colspan=1 rowspan=1 > 2,453,002 </td><td colspan=1 rowspan=1 > 18.2 </td></tr>
<tr> <td colspan=1 rowspan=1 > Blank ballots </td><td colspan=1 rowspan=1 > 856,664 </td><td colspan=1 rowspan=1 > – </td></tr>
<tr> <td colspan=1 rowspan=1 > Invalid votes </td><td colspan=1 rowspan=1 > 124,523 </td><td colspan=1 rowspan=1 > – </td></tr>
<tr> <td colspan=1 rowspan=1 > Total </td><td colspan=1 rowspan=1 > 14,491,852 </td><td colspan=1 rowspan=1 > 100 </td></tr>
<tr> <td colspan=1 rowspan=1 > Registered voters/turnout </td><td colspan=1 rowspan=1 > 34,692,491 </td><td class="highlighted"  colspan=1 rowspan=1 > 41.8 </td></tr>
<tr> <td colspan=3 rowspan=1 > Source: Nohlen & Stöver, European Election Database </td></tr>
</table>
Question:
What percentage approved the 2005 Spanish European Constitution referendum, and what was the percentage of voter turnout?
Answer:
Constitution of the European Union was approved by 81.8% of voters, turnout was 41.8%.