{% for year in range(2099, 2010, -1) %}

  {% set items = [] %}

  {% for article in data.articles %}
    {% if article.date|date('Y') == year %}
      {% set items = items|merge([article]) %}
    {% endif %}
  {% endfor %}

  {% if items %}
    <h2 class="year-title">{{ year }}</h2>
    {% for article in items %}
      <h3 class="article-title">
        <a href="{{ article.url }}">{{ article.title }}</a>
      </h3>
    {% endfor %}
  {% endif %}

{% endfor %}