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:
Trail Life USA
Table title:
History
Table:
<table id='hittask' contenteditable='False'>
<tr> <th colspan=1 rowspan=1 > Year </th><th colspan=1 rowspan=1 > Units </th><th colspan=1 rowspan=1 > Members </th></tr>
<tr> <td colspan=1 rowspan=1 > 2014 </td><td colspan=1 rowspan=1 > 500 </td><td colspan=1 rowspan=1 > N/A </td></tr>
<tr> <td class="highlighted"  colspan=1 rowspan=1 > 2015 </td><td class="highlighted"  colspan=1 rowspan=1 > 524 </td><td class="highlighted"  colspan=1 rowspan=1 > 20,000 </td></tr>
<tr> <td colspan=1 rowspan=1 > 2017 </td><td colspan=1 rowspan=1 > 700 </td><td colspan=1 rowspan=1 > 26,000 </td></tr>
</table>
Question:
How many people did Trail Life USA have in 2015?
Answer:
As of 2015, Trail Life USA has 524 troops with 20,000 members.