diff --git a/charting/just_ours.xsl b/charting/just_ours.xsl
new file mode 100644
index 00000000..5c7323c0
--- /dev/null
+++ b/charting/just_ours.xsl
@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+
+	just_ours.xsl
+
+	Remove SAML entities registered other than by the UK federation.
+
+	Leave in entities without registrationAuthority so that this still does
+	the right thing with older aggregates which don't have MDRPI metadata.
+
+	Author: Ian A. Young <ian@iay.org.uk>
+
+-->
+<xsl:stylesheet version="1.0"
+	xmlns:md="urn:oasis:names:tc:SAML:2.0:metadata"
+	xmlns:mdrpi="urn:oasis:names:tc:SAML:metadata:rpi"
+	xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
+
+	<!--
+		Force UTF-8 encoding for the output.
+	-->
+	<xsl:output omit-xml-declaration="no" method="xml" encoding="UTF-8"/>
+
+	<!--
+		Discard entities not registered by the UK federation.
+	-->
+	<xsl:template match="md:EntityDescriptor
+		[not(descendant::mdrpi:RegistrationInfo/@registrationAuthority='http://ukfederation.org.uk')]">
+		<!-- do nothing -->
+	</xsl:template>
+
+	<!--By default, copy text blocks, comments and attributes unchanged.-->
+	<xsl:template match="text()|comment()|@*">
+		<xsl:copy/>
+	</xsl:template>
+
+	<!--By default, copy all elements from the input to the output, along with their attributes and contents.-->
+	<xsl:template match="*">
+		<xsl:copy>
+			<xsl:apply-templates select="node()|@*"/>
+		</xsl:copy>
+	</xsl:template>
+
+</xsl:stylesheet>
diff --git a/charting/sizes.pl b/charting/sizes.pl
index a7b19fd5..0efab7f2 100755
--- a/charting/sizes.pl
+++ b/charting/sizes.pl
@@ -3,7 +3,9 @@
 #
 # sizes.pl
 #
+use lib "../build";
 use File::stat;
+use Xalan;
 use Months;
 
 # Parse command line arguments
@@ -20,14 +22,41 @@
 
 # ingest files
 foreach $month (@months) {
+	print "Processing $month\n";
+
+	#
+	# Process the archived file, representing all entities,
+	# including those imported from other federations.
+	#
 	my $fn = "cache/$month.xml";
+	my $stat = stat($fn);
+	my $all_size = $stat->size;
+	my $all_count = int(`grep '</Entity' $fn | wc -l`);
+	my $all_ratio = int($all_size/$all_count);
+	push @all_sizes,  $all_size;
+	push @all_counts, $all_count;
+	push @all_ratios, $all_ratio;
+
+	#
+	# Now generate a reduced version of the archived
+	# file that contains only UK federation registered entities.
+	#
+	my $command = xalanCall . " -IN $fn -XSL just_ours.xsl -OUT temp.tmp";
+	# print "command is $command\n";
+	system($command); # || print "ignoring claimed failure in sub command\n";
+	# print "Xalan run on $fn\n";
+
+	#
+	# Process the reduced version of the archived file.
+	#
+	$fn = "temp.tmp";
 	$stat = stat($fn);
-	$size = $stat->size;
-	$wc = int(`grep '</Entity' $fn | wc -l`);
-	$ratio = int($size/$wc);
-	push @sizes, $size;
-	push @counts, $wc;
-	push @ratios, $ratio;
+	my $our_size = $stat->size;
+	my $our_count = int(`grep '</Entity' $fn | wc -l`);
+	my $our_ratio = int($our_size/$our_count);
+	push @our_sizes,  $our_size;
+	push @our_counts, $our_count;
+	push @our_ratios, $our_ratio;
 }
 
 print "months\n";
@@ -35,29 +64,36 @@
 	print "$month\n";
 }
 
-print "size\n";
-foreach $size (@sizes) {
+print "sizeM (all)\n";
+foreach $size (@all_sizes) {
+	$size /= 1000000;
 	print "$size\n";
 }
 
-print "sizeM\n";
-foreach $size (@sizes) {
+print "sizeM (UK)\n";
+foreach $size (@our_sizes) {
 	$size /= 1000000;
 	print "$size\n";
 }
 
-print "entities\n";
-foreach $count (@counts) {
+print "entities (all)\n";
+foreach $count (@all_counts) {
 	print "$count\n";
 }
 
-print "ratio\n";
-foreach $ratio (@ratios) {
+print "entities (UK)\n";
+foreach $count (@our_counts) {
+	print "$count\n";
+}
+
+print "ratioK (all)\n";
+foreach $ratio (@all_ratios) {
+	$ratio /= 1000;
 	print "$ratio\n";
 }
 
-print "ratioK\n";
-foreach $ratio (@ratios) {
+print "ratioK (UK)\n";
+foreach $ratio (@our_ratios) {
 	$ratio /= 1000;
 	print "$ratio\n";
 }