Update copyright year
diff --git a/source/_includes/footer.html b/source/_includes/footer.html
index 71930dd..ba54499 100644
--- a/source/_includes/footer.html
+++ b/source/_includes/footer.html
@@ -1,7 +1,7 @@
 
 <footer class="container">
   <div class="col-md-12">
-    Copyright &copy; 2000-2018 <a href="http://www.apache.org/">The Apache Software Foundation </a>.
+    Copyright &copy; 2000-2021 <a href="http://www.apache.org/">The Apache Software Foundation </a>.
     All Rights Reserved.
   </div>
   <div class="col-md-12">