>$</span><span class="va">var.x</span><span class="op">)</span><span class="op">)</span>,fill<span class="op">=</span><span class="st">"grey"</span>, alpha<span class="op">=</span><span class="fl">0.9</span><span class="op">)</span> <span class="op">+</span></span>
<span>  <span class="fu"><a href="https://ggplot2.tidyverse.org/reference/geom_path.html" class="external-link">geom_line</a></span><span class="op">(</span><span class="fu"><a href="https://ggplot2.tidyverse.org/reference/aes.html" class="extern