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 Majority Leaders of the Minnesota Senate
Table title:

Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Name </th><th colspan=1 rowspan=1 > Took Office </th><th colspan=1 rowspan=1 > Left Office </th><th colspan=1 rowspan=1 > Party/Caucus </th></tr>
<tr> <td colspan=1 rowspan=1 > Charles N. Orr </td><td colspan=1 rowspan=1 > 1933 </td><td colspan=1 rowspan=1 > 1949 </td><td colspan=1 rowspan=1 > Conservative </td></tr>
<tr> <td colspan=1 rowspan=1 > Archie H. Miller </td><td colspan=1 rowspan=1 > 1949 </td><td colspan=1 rowspan=1 > 1959 </td><td colspan=1 rowspan=1 > Conservative </td></tr>
<tr> <td colspan=1 rowspan=1 > John M. Zwach </td><td colspan=1 rowspan=1 > 1959 </td><td colspan=1 rowspan=1 > 1967 </td><td colspan=1 rowspan=1 > Conservative </td></tr>
<tr> <td colspan=1 rowspan=1 > Stanley W. Holmquist </td><td colspan=1 rowspan=1 > 1967 </td><td colspan=1 rowspan=1 > 1973 </td><td colspan=1 rowspan=1 > Conservative </td></tr>
<tr> <td colspan=1 rowspan=1 > Nick Coleman </td><td colspan=1 rowspan=1 > 1973 </td><td colspan=1 rowspan=1 > 1981 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td colspan=1 rowspan=1 > Roger Moe </td><td colspan=1 rowspan=1 > 1981 </td><td colspan=1 rowspan=1 > 2003 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td colspan=1 rowspan=1 > John Hottinger </td><td colspan=1 rowspan=1 > 2003 </td><td colspan=1 rowspan=1 > 2004 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td colspan=1 rowspan=1 > Dean Johnson </td><td colspan=1 rowspan=1 > 2004 </td><td colspan=1 rowspan=1 > 2007 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td colspan=1 rowspan=1 > Larry Pogemiller </td><td colspan=1 rowspan=1 > 2007 </td><td colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Amy Koch </td><td colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > Republican </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > Dave Senjem </td><td class="highlighted"  colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > 2013 </td><td colspan=1 rowspan=1 > Republican </td></tr>
<tr> <td colspan=1 rowspan=1 > Tom Bakk </td><td colspan=1 rowspan=1 > 2013 </td><td colspan=1 rowspan=1 > 2017 </td><td colspan=1 rowspan=1 > Democratic-Farmer-Labor </td></tr>
<tr> <td colspan=1 rowspan=1 > Paul Gazelka </td><td colspan=1 rowspan=1 > 2017 </td><td colspan=1 rowspan=1 > Incumbent </td><td colspan=1 rowspan=1 > Republican </td></tr>
</table>
Question:
Who replaced Amy Koch as majority leader and when?
Answer:
In 2011, Senjem was elected majority leader after the previous majority leader, Amy Koch.