<span class="va">val_norm</span>,color<span class="op">=</span><span class="va">`Vehicle type`</span><span class="op">)</span><span class="op">)</span> <span class="op">+</span></span>
<span>  <span class="fu"><a href="https://ggplot2.tidyverse.org/reference/geom_smooth.html" class="external-link">geom_smooth</a></span><span class="op">(</span>span<span class="op">=</span><span class="fl">0.2</span>,method <span class="op">=</span> <span class="st">'loess'</span>, formula <span class="op">=</span> <span cla