diff --git a/data/xslt/bison.xsl b/data/xslt/bison.xsl
index 6d96e014..ce3fe0f3 100644
--- a/data/xslt/bison.xsl
+++ b/data/xslt/bison.xsl
@@ -2,6 +2,8 @@
 
 <!--
     bison.xsl - common templates for Bison XSLT.
+    $Id$
+
     Copyright (C) 2007 Free Software Foundation, Inc.
 
     This file is part of Bison, the GNU Compiler Compiler.
@@ -24,6 +26,10 @@
   xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
   xmlns:bison="http://www.gnu.org/software/bison/">
 
+<xsl:key name="bison:ruleNumber"
+	 match="/bison-xml-report/grammar/rules/rule"
+	 use="@number"/>
+
 <!-- For the specified state, output: #sr-conflicts,#rr-conflicts -->
 <xsl:template match="state" mode="bison:count-conflicts">
   <xsl:variable name="transitions" select="actions/transitions"/>