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:
Netball Quad Series
Table title:
Results
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Series </th><th colspan=1 rowspan=1 > Winner </th><th colspan=1 rowspan=1 > Second </th><th colspan=1 rowspan=1 > Third </th><th colspan=1 rowspan=1 > Fourth </th></tr>
<tr> <td colspan=1 rowspan=1 > 2016 </td><td colspan=1 rowspan=1 > Australia </td><td colspan=1 rowspan=1 > New Zealand </td><td colspan=1 rowspan=1 > England </td><td colspan=1 rowspan=1 > South Africa </td></tr>
<tr> <td colspan=1 rowspan=1 > 2017 (I) </td><td colspan=1 rowspan=1 > Australia </td><td colspan=1 rowspan=1 > New Zealand </td><td colspan=1 rowspan=1 > England </td><td colspan=1 rowspan=1 > South Africa </td></tr>
<tr> <td colspan=1 rowspan=1 > 2017 (II) </td><td colspan=1 rowspan=1 > New Zealand </td><td colspan=1 rowspan=1 > Australia </td><td colspan=1 rowspan=1 > England </td><td colspan=1 rowspan=1 > South Africa </td></tr>
<tr> <td colspan=1 rowspan=1 > 2018 (I) </td><td colspan=1 rowspan=1 > Australia </td><td colspan=1 rowspan=1 > England </td><td colspan=1 rowspan=1 > New Zealand </td><td colspan=1 rowspan=1 > South Africa </td></tr>
<tr> <td colspan=1 rowspan=1 > 2018 (II) </td><td colspan=1 rowspan=1 > Australia </td><td colspan=1 rowspan=1 > England </td><td colspan=1 rowspan=1 > New Zealand </td><td colspan=1 rowspan=1 > South Africa </td></tr>
<tr> <td colspan=1 rowspan=1 > 2019 (I) </td><td class="highlighted"  colspan=1 rowspan=1 > Australia </td><td class="highlighted"  colspan=1 rowspan=1 > England </td><td class="highlighted"  colspan=1 rowspan=1 > New Zealand </td><td class="highlighted"  colspan=1 rowspan=1 > South Africa </td></tr>
</table>
Question:
Which countries are included in the Netball Quad Series?
Answer:
The Netball Quad Series was contested by the national teams of Australia, England, New Zealand and South Africa.