an class='kw'>stack_by</span> <span class='kw'>=</span> <span class='no'>insured</span>,
  <span class='kw'>count</span> <span class='kw'>=</span> <span class='no'>prop</span>,
  <span class='kw'>proportion</span> <span class='kw'>=</span> <span class='fl'>TRUE</span>
)</div><div class='img'><img src='age_pyramid-4.png' alt='' width='700' height='433' /></div><div class='input'>
<span class='co'># from linelist data --------------------------------------------------------</span>
<span class='fu'><a href='ht