Display more working papers on the index page

wp/index.md

@@ -10,7 +10,7 @@ title: Working Papers
 {% endfor %}
 
 <ol>
-{% for wp in site.data.wp limit:5 %}
+{% for wp in site.data.wp limit:7 %}
 <li value = "{{ wpn }}">
   {{ wp.authors }} ({{ wp.year }}), “<a href="{{ wp.url }}">{{ wp.title }}</a>”
   {% if wp.source_url %}(<a href="{{ wp.source_url }}">source</a>){% endif %}