ts = sum(flights)))</span></span>
<span><span class="va">flights</span> <span class="op"><a href="https://magrittr.tidyverse.org/reference/pipe.html" class="external-link">%&gt;%</a></span> </span>
<span>  <span class="fu"><a href="../reference/summarise_dt.html">summarise_dt</a></span><span class="op">(</span>by <span class="op">=</span> <span class="fu">.</span><span class="op">(</span><span class="va">year</span>,<span class="va">month</span>,<span class="va">day</span><span class="op">)</span>,flights <