an class="kw"><a href="https://rdrr.io/r/base/library.html" class="external-link">library</a></span><span class="op">(</span><span class="va"><a href="https://purrr.tidyverse.org/" class="external-link">purrr</a></span><span class="op">)</span></span></span>
<span class="r-in"><span></span></span>
<span class="r-in"><span><span class="co"># Dates -&gt; duration in years</span></span></span>
<span class="r-in"><span><span class="fu">calc_duration</span><span class="op">(</span></span></span>
<span class="r-i