Most of the report related REST API returns an XML format data.
You may do a 'GET' request to below URL (can use curl command or just input the url directly in your browser)
http://demo.pmease.com/rest/pmd/records/agg_stats/1/PMD%20DEFAULT?filters=day>'2012-06-08'
and the sample data looks like:
<report name="agg_stats" version="2.1" locale="en_US">
<row ID="51" day="2012-06-15T00:00:00.000Z" packages="33" files="63" violations="163" highs="0" mediums="13" normals="121" lows="29" added="87" fixed="84" notFixed="76"/>
<row ID="52" day="2012-06-18T00:00:00.000Z" packages="33" files="63" violations="163" highs="0" mediums="13" normals="121" lows="29" added="87" fixed="84" notFixed="76"/>
<row ID="53" day="2012-07-09T00:00:00.000Z" packages="33" files="63" violations="163" highs="0" mediums="13" normals="121" lows="29" added="87" fixed="84" notFixed="76"/>
<row ID="54" day="2012-07-11T00:00:00.000Z" packages="33" files="63" violations="163" highs="0" mediums="13" normals="121" lows="29" added="87" fixed="84" notFixed="76"/>
...
</report>
visit
http://your-quickbuild/rest/pmd/help for all available REST functions and their related params.