diff --git a/chart.module b/chart.module
index 09e2ceb..31360dc 100644
--- a/chart.module
+++ b/chart.module
@@ -268,12 +268,12 @@ function chart_build($chart) {
   $data = array();
 
   // Must have a chart id
-  if (!strlen(trim($chart['#chart_id']))){
+  if (!strlen(trim($chart['#chart_id']))) {
     return FALSE;
   }
 
   // We need data :)
-  if (!count($chart['#data']) || !is_array($chart['#data'])){
+  if (!count($chart['#data']) || !is_array($chart['#data'])) {
     return FALSE;
   }
 
@@ -284,15 +284,15 @@ function chart_build($chart) {
   }
 
   // Adjust resolution
-  if (isset($chart['#adjust_resolution'])){
-    if ($chart['#adjust_resolution'] === TRUE){
+  if (isset($chart['#adjust_resolution'])) {
+    if ($chart['#adjust_resolution'] === TRUE) {
       _chart_adjust_resolution($chart['#chart_id'], $chart['#data']);
     }
-    elseif ($chart['#adjust_resolution']['#adjust'] == TRUE){
+    elseif ($chart['#adjust_resolution']['#adjust'] == TRUE) {
       _chart_adjust_resolution($chart['#chart_id'], $chart['#data'], $chart['#adjust_resolution']['#max']);
     }
   }
-
+  
   $data['chd'] = 't:' . _chart_encode_data($chart['#data']);
 
   _chart_append('cht',   $chart['#type'],                    $data);
@@ -311,6 +311,7 @@ function chart_build($chart) {
   _chart_append('chbh',  $chart['#bar_size'],                $data);
   _chart_append('chld',  $chart['#countries'],               $data);
   _chart_append('chtm',  $chart['#georange'],                $data);
+  _chart_append('chma',  $chart['#margins'],                 $data);
 
   $charts[$chart['#chart_id']] = drupal_query_string_encode($data);
 
@@ -412,42 +413,53 @@ function _chart_encode_data($data) {
  * for the selected encoding type.
  */
 function _chart_adjust_resolution($chart_id, &$data, $max_value = NULL) {
-  static $max;
+  static $max, $min;
 
-  if (count($data)){
+  if (count($data)) {
+    list ($tmax, $tmin) = _chart_get_max_min($data);
     // Set max data value
-    if (!isset($max[$chart_id])){
-      $max[$chart_id] = isset($max_value) ? $max_value : _chart_get_max($data);
+    if (!isset($max[$chart_id])) {
+      $max[$chart_id] = isset($max_value) ? $max_value : $tmax;
+    }
+    // Set min data value
+    if (!isset($min[$chart_id])) {
+      $min[$chart_id] = $tmin;
     }
+    
+    $range = $max[$chart_id] - $min[$chart_id];
 
     // Encoding resolution
     $resoluton = 100;
-
-    // When the max is larger than the resolution
+    
+    // Bump: add this to values to make zero the new baseline
+    $bump = 0 - $min[$chart_id];
+    
+    // When the range is larger than the resolution
     // we need to scale down the values
-    if ($max[$chart_id] > $resoluton){
-      $divider = round($max[$chart_id] / $resoluton, 1);
+    if ($range > $resoluton) {
+      $divider = round($range / $resoluton, 1);
     }
     else {
-      $multiplier = round($resoluton / $max[$chart_id], 1);
+      $multiplier = round($resoluton / $range, 1);
     }
 
-    foreach($data AS $k => $v){
-      if (is_array($v)){
+    foreach ($data as $k => $v) {
+      if (is_array($v)) {
         _chart_adjust_resolution($chart_id, $data[$k]);
       }
       else {
-        if ($v != 'NULL' && $v > 0){
+        if ($v != 'NULL') {
+          $v += $bump;
           // Adjust values
-          if ($v >= $max){
+          if ($v >= $max[$chart_id] + $bump){
             $data[$k] = $resoluton;
           }
           else {
             // Multiply or divide data values to adjust them to the resolution
-            if (isset($divider)){
+            if (isset($divider)) {
               $data[$k] = floor($v / $divider);
             }
-            elseif (isset($multiplier)){
+            elseif (isset($multiplier)) {
               $data[$k] = floor($v * $multiplier);
             }
             else {
@@ -471,6 +483,13 @@ function _chart_append($attr, $value, &$data) {
   }
 
   switch($attr) {
+    // Margins
+    case 'chma':
+      // Remove any whitespace from this value
+      // Otherwise these spaces are encoded and the margins will not work
+      $data[$attr] = str_replace(" ", "", $value);
+      break;
+      
     // Type
     case 'cht':
       $data[$attr] = $value;
@@ -587,7 +606,7 @@ function _chart_append($attr, $value, &$data) {
       if (!isset($data[$attr])) {
         $data[$attr] = '';
       }
-      $data[$attr] .= implode(',', array($value['#size'], $value['#spacing']));
+      $data[$attr] .= implode(',', array($value['#size'], $value['#spacing'], $value['#group_spacing']));
       break;
 
      // Mixed axis positions, labels and styles
@@ -697,22 +716,55 @@ function _chart_append($attr, $value, &$data) {
 /**
  * Return the max value of a single level array.
  */
-function _chart_get_max($array) {
+function _chart_get_max_min($array) {
+
+  // if first element is array, assume we have array of arrays
+  if (is_array($array[0])) {
+
+    // loop through each sub-array
+    foreach ($array as $k => $v) {
+      if (is_array($v)) {
+        // initialize max/min values 1st time through
+        if ($k == 0) {
+          $max = max($v);
+          $min = min($v);
+        }
+        else {
+          if (max($v) > $max) {
+            $max = max($v);
+          }
+          if (min($v) < $min) {
+            $min = min($v);
+          }
+        }
+      }
+    }
+    
+  }
+  else {
+    // Just a single-level array
+    $max = max($array);
+    $min = min($array);
+  }
+  
+/*
   rsort($array, SORT_NUMERIC);
   $max = is_array($array[0]) ? 1 : $array[0];
 
-  if (count($array)){
-    foreach($array AS $k => $v){
-      if (is_array($v)){
+  if (count($array)) {
+    foreach($array AS $k => $v) {
+      if (is_array($v)) {
         rsort($v, SORT_NUMERIC);
-        if ($v[0] > $max){
+        if ($v[0] > $max) {
           $max = $v[0];
         }
       }
     }
   }
+*/
+
+  return array($max, $min);
 
-  return $max;
 }
 
 /**
@@ -1066,10 +1118,11 @@ function chart_range_marker($start, $end, $virtical = TRUE, $color = '000000') {
  *
  * @return array
  */
-function chart_bar_size($size = 40, $spacing = 20) {
+function chart_bar_size($size = 40, $spacing = 20, $group_spacing = 30) {
   return array(
-      '#size'    => $size,
-      '#spacing' => $spacing,
+      '#size'          => $size,
+      '#spacing'       => $spacing,
+      '#group_spacing' => $group_spacing,
     );
 }