ll the investors are active on the whole period of analysis.</p>
<div class="sourceCode" id="cb6"><pre class="downlit sourceCode r">
<code class="sourceCode R"><span class="co"># number of transactions of each investor over years</span>
<span class="va">trx</span> <span class="op"><a href="../reference/pipe.html">%&gt;%</a></span> 
  <span class="fu">dplyr</span><span class="fu">::</span><span class="fu"><a href="https://dplyr.tidyverse.org/reference/mutate.html" class="external-link">mutate</a></span><span