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:
U15 Group of Canadian Research Universities
Table title:
Membership
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Institution </th><th colspan=1 rowspan=1 > City </th><th colspan=1 rowspan=1 > Province </th><th colspan=1 rowspan=1 > Total students </th><th colspan=1 rowspan=1 > Established </th><th colspan=1 rowspan=1 > Year joined </th><th colspan=1 rowspan=1 > Sponsored research income (thousands) </th></tr>
<tr> <td colspan=1 rowspan=1 > University of Alberta </td><td colspan=1 rowspan=1 > Edmonton </td><td colspan=1 rowspan=1 > Alberta </td><td colspan=1 rowspan=1 > 38,820 </td><td colspan=1 rowspan=1 > 1908 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $513,313 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of British Columbia </td><td colspan=1 rowspan=1 > Vancouver </td><td colspan=1 rowspan=1 > British Columbia </td><td colspan=1 rowspan=1 > 60,560 </td><td colspan=1 rowspan=1 > 1908 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $577,190 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of Calgary </td><td colspan=1 rowspan=1 > Calgary </td><td colspan=1 rowspan=1 > Alberta </td><td colspan=1 rowspan=1 > 32,710 </td><td colspan=1 rowspan=1 > 1966 </td><td colspan=1 rowspan=1 > 2006 </td><td colspan=1 rowspan=1 > $380,388 </td></tr>
<tr> <td colspan=1 rowspan=1 > Dalhousie University </td><td colspan=1 rowspan=1 > Halifax </td><td colspan=1 rowspan=1 > Nova Scotia </td><td colspan=1 rowspan=1 > 18,940 </td><td colspan=1 rowspan=1 > 1818 </td><td colspan=1 rowspan=1 > 2006 </td><td colspan=1 rowspan=1 > $150,038 </td></tr>
<tr> <td colspan=1 rowspan=1 > Université Laval </td><td colspan=1 rowspan=1 > Quebec City </td><td colspan=1 rowspan=1 > Quebec </td><td colspan=1 rowspan=1 > 43,560 </td><td colspan=1 rowspan=1 > 1663 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $356,675 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > University of Manitoba </td><td colspan=1 rowspan=1 > Winnipeg </td><td colspan=1 rowspan=1 > Manitoba </td><td colspan=1 rowspan=1 > 28,870 </td><td colspan=1 rowspan=1 > 1877 </td><td class="highlighted"  colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > $187,444 </td></tr>
<tr> <td colspan=1 rowspan=1 > McGill University </td><td colspan=1 rowspan=1 > Montreal </td><td colspan=1 rowspan=1 > Quebec </td><td colspan=1 rowspan=1 > 38,580 </td><td colspan=1 rowspan=1 > 1821 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $515,302 </td></tr>
<tr> <td colspan=1 rowspan=1 > McMaster University </td><td colspan=1 rowspan=1 > Hamilton </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 32,600 </td><td colspan=1 rowspan=1 > 1887 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $379,959 </td></tr>
<tr> <td colspan=1 rowspan=1 > Université de Montréal </td><td colspan=1 rowspan=1 > Montreal </td><td colspan=1 rowspan=1 > Quebec </td><td colspan=1 rowspan=1 > 48,330 </td><td colspan=1 rowspan=1 > 1878 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $536,238 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of Ottawa </td><td colspan=1 rowspan=1 > Ottawa </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 42,200 </td><td colspan=1 rowspan=1 > 1848 </td><td colspan=1 rowspan=1 > 2006 </td><td colspan=1 rowspan=1 > $325,969 </td></tr>
<tr> <td colspan=1 rowspan=1 > Queen's University </td><td colspan=1 rowspan=1 > Kingston </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 28,140 </td><td colspan=1 rowspan=1 > 1841 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $207,034 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > University of Saskatchewan </td><td colspan=1 rowspan=1 > Saskatoon </td><td colspan=1 rowspan=1 > Saskatchewan </td><td colspan=1 rowspan=1 > 21,420 </td><td colspan=1 rowspan=1 > 1907 </td><td class="highlighted"  colspan=1 rowspan=1 > 2011 </td><td colspan=1 rowspan=1 > $186,261 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of Toronto </td><td colspan=1 rowspan=1 > Toronto </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 89,540 </td><td colspan=1 rowspan=1 > 1827 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $1,147,584 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of Waterloo </td><td colspan=1 rowspan=1 > Waterloo </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 39,200 </td><td colspan=1 rowspan=1 > 1956 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $189,333 </td></tr>
<tr> <td colspan=1 rowspan=1 > University of Western Ontario </td><td colspan=1 rowspan=1 > London </td><td colspan=1 rowspan=1 > Ontario </td><td colspan=1 rowspan=1 > 32,500 </td><td colspan=1 rowspan=1 > 1878 </td><td colspan=1 rowspan=1 > 1991 </td><td colspan=1 rowspan=1 > $249,669 </td></tr>
</table>
Question:
What happened to the size of the U15 Group of Canadian Research Universities in 2015?
Answer:
In 2011, the U15 Group of Canadian Research Universities grew its membership with the addition of the University of Manitoba and the University of Saskatchewan.