--- 
+++ 
@@ -93,13 +93,15 @@
 
 # Scale ddrss data
 print "len:$#ddates\nmin:$drss_min\nmax:$drss_max\n";
-my $scale = ($ddrss_max - $ddrss_min) / ($drss_max - $drss_min);
-for(my $i = 0; $i <= $#ddates; $i++) {
-	$table{$ddates[$i]}{'drss'} -= $drss_min;
-	$table{$ddates[$i]}{'drss'} *= $scale;
-	$table{$ddates[$i]}{'drss'} += $ddrss_min;
+my $constant = ($drss_max == $drss_min);
+if(! $constant) {
+	my $scale = ($ddrss_max - $ddrss_min) / ($drss_max - $drss_min);
+	for(my $i = 0; $i <= $#ddates; $i++) {
+		$table{$ddates[$i]}{'drss'} -= $drss_min;
+		$table{$ddates[$i]}{'drss'} *= $scale;
+		$table{$ddates[$i]}{'drss'} += $ddrss_min;
+	}
 }
-
 
 ### Write to cvs file
 close($data_file);
@@ -116,20 +118,22 @@
 	} else {
 		printf $data_file "?0";
 	}
-	print $data_file "\t";
-	if(defined $table{$date}{'drss'}) {
-		printf $data_file "%i", $table{$date}{'drss'};
-	} else {
-		printf $data_file "?0";
+	if(!$constant) {
+		print $data_file "\t";
+		if(defined $table{$date}{'drss'}) {
+			printf $data_file "%i", $table{$date}{'drss'};
+		} else {
+			printf $data_file "?0";
+		}
+		print $data_file "\t";
+		if(defined $table{$date}{'ddrss'}) {
+			printf $data_file "%i", $table{$date}{'ddrss'};
+		} else {
+			printf $data_file "?0";
+		}
+
+		print $data_file "\n";
 	}
-	print $data_file "\t";
-	if(defined $table{$date}{'ddrss'}) {
-		printf $data_file "%i", $table{$date}{'ddrss'};
-	} else {
-		printf $data_file "?0";
-	}
-
-	print $data_file "\n";
 }
 
 $rss_min -= ($rss_max - $rss_min) / 5;