diff --git a/_includes/package-nav.html b/_includes/package-nav.html
index e400fd8..1d63b42 100644
--- a/_includes/package-nav.html
+++ b/_includes/package-nav.html
@@ -1,8 +1,8 @@
+<li><a href="04-tidy.html">Tidy data</a></li>
 <!--
 <li><a href="01-introduction.html">Introduction to data science</a></li>
 <li><a href="02-visualize.html">Visualize data</a></li>
 <li><a href="03-transform.html">Transform data</a></li>
-<li><a href="04-tidy.html">Tidy data</a></li>
 <li><a href="05-import.html">Import data</a></li>
 <li><a href="06-dates.html">Dates and times</a></li>
 <li><a href="07-strings.html">Regular expresssions</a></li>