Revised year listing that is more robust to changes-

_layouts/post-index.html

@@ -34,16 +34,13 @@
   </div>
   <div id="index">
     <h1>{{ page.title }}</h1>
+    {% capture written_year %}'None'{% endcapture %}
     {% for post in site.posts %}  
-    {% unless post.next %}
-      <h3>{{ post.date | date: '%Y' }}</h3>
-      {% else %}
       {% capture year %}{{ post.date | date: '%Y' }}{% endcapture %}
-        {% capture nyear %}{{ post.next.date | date: '%Y' }}{% endcapture %}
-        {% if year != nyear %}
-          <h3>{{ post.date | date: '%Y' }}</h3>
+      {% if year != written_year %}
+        <h3>{{ year }}</h3>
+      {% capture written_year %}{{ year }}{% endcapture %}
       {% endif %}
-      {% endunless %}
       <article>
         {% if post.link %}
           <h2 class="link-post"><a href="{{ site.url }}{{ post.url }}" title="{{ post.title }}">{{ post.title }}</a> <a href="{{ post.link }}" target="_blank" title="{{ post.title }}"><i class="fa fa-link"></i></a></h2>