9-1"><a href="controlling-tooltips.html#cb219-1"></a><span class="kw">library</span>(scales)</span>
<span id="cb219-2"><a href="controlling-tooltips.html#cb219-2"></a>p &lt;-<span class="st"> </span><span class="kw">ggplot</span>(txhousing, <span class="kw">aes</span>(date, median)) <span class="op">+</span><span class="st"> </span></span>
<span id="cb219-3"><a href="controlling-tooltips.html#cb219-3"></a><span class="st">  </span><span class="kw">geom_line</span>(<span class="kw">aes</span>(</span>
<span i