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:
Helen Slatter
Table title:
International competitions
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Year </th><th colspan=1 rowspan=1 > Competition </th><th colspan=1 rowspan=1 > Venue </th><th colspan=1 rowspan=1 > Position </th><th colspan=1 rowspan=1 > Event </th><th colspan=1 rowspan=1 > Notes </th></tr>
<tr> <th colspan=6 rowspan=1 > Representing Great Britain / England </th></tr>
<tr> <td colspan=1 rowspan=1 > 1988 </td><td colspan=1 rowspan=1 > Olympic Games </td><td colspan=1 rowspan=1 > Seoul, South Korea </td><td colspan=1 rowspan=1 > 22nd </td><td colspan=1 rowspan=1 > 200 m backstroke </td><td colspan=1 rowspan=1 > 2:21.66 </td></tr>
<tr> <td colspan=1 rowspan=1 > 1990 </td><td colspan=1 rowspan=1 > Commonwealth Games </td><td colspan=1 rowspan=1 > Auckland, New Zealand </td><td colspan=1 rowspan=1 > 9th </td><td colspan=1 rowspan=1 > 100 m backstroke </td><td colspan=1 rowspan=1 > 1:06.17 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=3 > 1991 </td><td class="highlighted"  colspan=1 rowspan=3 > World Championships </td><td colspan=1 rowspan=3 > Perth, Australia </td><td colspan=1 rowspan=1 > 14th </td><td colspan=1 rowspan=1 > 100 m backstroke </td><td colspan=1 rowspan=1 > 1:05.20 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 11th </td><td class="highlighted"  colspan=1 rowspan=1 > 200 m backstroke </td><td colspan=1 rowspan=1 > 2:16.83 </td></tr>
<tr> <td colspan=1 rowspan=1 > 13th </td><td colspan=1 rowspan=1 > 400 m medley </td><td colspan=1 rowspan=1 > 4:55.77 </td></tr>
<tr> <td colspan=1 rowspan=3 > 1992 </td><td colspan=1 rowspan=3 > Olympic Games </td><td colspan=1 rowspan=3 > Barcelona, Spain </td><td colspan=1 rowspan=1 > 24th </td><td colspan=1 rowspan=1 > 200 m butterfly </td><td colspan=1 rowspan=1 > 2:20.45 </td></tr>
<tr> <td colspan=1 rowspan=1 > 26th </td><td colspan=1 rowspan=1 > 200m medley </td><td colspan=1 rowspan=1 > 2:22.04 </td></tr>
<tr> <td colspan=1 rowspan=1 > 23rd </td><td colspan=1 rowspan=1 > 400 m medley </td><td colspan=1 rowspan=1 > 4:58.24 </td></tr>
<tr> <td colspan=1 rowspan=5 > 1994 </td><td colspan=1 rowspan=5 > Commonwealth Games </td><td colspan=1 rowspan=5 > Victoria, Canada </td><td colspan=1 rowspan=1 > 10th </td><td colspan=1 rowspan=1 > 100 m backstoke </td><td colspan=1 rowspan=1 > 1:04.70 </td></tr>
<tr> <td colspan=1 rowspan=1 > 12th </td><td colspan=1 rowspan=1 > 100 m butterfly </td><td colspan=1 rowspan=1 > 1:04.55 </td></tr>
<tr> <td colspan=1 rowspan=1 > 5th </td><td colspan=1 rowspan=1 > 200 m butterfly </td><td colspan=1 rowspan=1 > 2:16.15 </td></tr>
<tr> <td colspan=1 rowspan=1 > 9th </td><td colspan=1 rowspan=1 > 200 m medley </td><td colspan=1 rowspan=1 > 2:21.46 </td></tr>
<tr> <td colspan=1 rowspan=1 > 7th </td><td colspan=1 rowspan=1 > 400 m medley </td><td colspan=1 rowspan=1 > 4:58.33 </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=2 > 1996 </td><td class="highlighted"  colspan=1 rowspan=2 > Olympic Games </td><td colspan=1 rowspan=2 > Atlanta, United States </td><td class="highlighted"  colspan=1 rowspan=1 > 13th </td><td class="highlighted"  colspan=1 rowspan=1 > 100 m backstroke </td><td colspan=1 rowspan=1 > 1:03.61 </td></tr>
<tr> <td colspan=1 rowspan=1 > 13th </td><td colspan=1 rowspan=1 > 4 × 100 m medley </td><td colspan=1 rowspan=1 > 1:03.87 </td></tr>
<tr> <td colspan=1 rowspan=1 > 1998 </td><td colspan=1 rowspan=1 > Commonwealth Games </td><td colspan=1 rowspan=1 > Kuala Lumpur, Malaysia </td><td colspan=1 rowspan=1 > 12th </td><td colspan=1 rowspan=1 > 100 m backstroke </td><td colspan=1 rowspan=1 > 1:04.98 </td></tr>
</table>
Question:
What was Helen Slatter's backstroke performance like in 1991 and 1996?
Answer:
Helen Slatter finished 11th in the 200m backstroke at the 1991 World Championships and 13th in the 100m backstroke at the 1996 Olympic Games.