                        &lt;NA&gt;</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 30                                  &lt;NA&gt;</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 31                                  &lt;NA&gt;</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 32                                  &lt;NA&gt;</span>
<span class="r-out co"><span class="r-pr">#&gt;</span> 33                                  &lt;NA&gt;</span>
<span class="r-out co"><span class