<div class="archive">
    <% let lastyear = 0; let lastmonth = -1; %>
    <aside class="menu">
        <% site.posts.sort('date', -1).each(function(post) { %>
            <% let year = post.date.year(); let month = post.date.month(); %>
            <% if (lastyear !== year || lastmonth !== month) { %>
                <% if (lastyear !== 0 || lastmonth !== -1){ %> 
                    </ul>
                <% } %>
                <p class="menu-label"><%- date(post.date, "YYYY.MMM"); %></p>
                <ul class="menu-list">
                <% lastyear = year; lastmonth = month; %>
            <% } %>
            <li>
                <a class="title" href="<%- url_for(post.path) %>">
                    <%= post.title %>
                </a>
            </li>
        <% }) %>
    </aside>
</div>