xxxxxxxxxx
<table border>
<caption>A more complex table</caption>
<th rowspan=2><th colspan=2>average<th rowspan=2>other<br>category<tr>
<th>height <th>weight <tr>
<th align=left>males <td>1.9 <td>0.003 <td>yyy <tr>
<th align=left>females <td>1.7 <td>0.002 <td>xxx
</table>