diff --git a/web/theme/templates/pages/api.html b/web/theme/templates/pages/api.html
index 4ea21e6..a5ef87e 100644
--- a/web/theme/templates/pages/api.html
+++ b/web/theme/templates/pages/api.html
@@ -68,6 +68,7 @@ <h3>{% trans %}Configuration parameters{% endtrans %}</h3>
             <li><code>ignore_empty_rows</code>: (default False) A boolean to set whether empty rows should raise errors, or be ignored.</li>
             <li><code>encoding</code>: (default None) A string that indicates the encoding of the data. Overrides automatic encoding detection.</li>
             <li><code>format</code>: (default 'csv') 'csv' or 'excel' - the format of the file.</li>
+            <li><code>report_type</code>: (default 'basic') 'basic' or 'grouped' - the formatting of report results.</li>
         </ul>
         <h3>{% trans %}Report structure{% endtrans %}</h3>
         <p>For details on the report structure, refer to the <a href="http://goodtables.readthedocs.org/en/latest/reports.html">{% trans %}Good Tables documentation{% endtrans %}</a>.</p>