=== modified file 'dhis-2/dhis-services/dhis-service-mapgeneration/src/main/java/org/hisp/dhis/mapgeneration/InternalMapLayer.java'
--- dhis-2/dhis-services/dhis-service-mapgeneration/src/main/java/org/hisp/dhis/mapgeneration/InternalMapLayer.java	2014-03-26 22:18:35 +0000
+++ dhis-2/dhis-services/dhis-service-mapgeneration/src/main/java/org/hisp/dhis/mapgeneration/InternalMapLayer.java	2014-06-17 12:03:00 +0000
@@ -362,14 +362,17 @@
 
         List<Double> values = getSortedMapObjectValues();
         
+        Assert.isTrue( values.size() > 0 );
+        
         int range = values.size() / length;
         
         for ( int i = 0; i < length; i++ )
         {
             int lowIndex = range * i;
-            int highIndex = lowIndex + range - 1;
+            int highIndex = Math.max( lowIndex + range - 1, 0 );
             
             double low = values.get( lowIndex );
+
             double high = values.get( highIndex );
             
             if ( length == i + 1 ) // At last position