diff --git a/src/main/java/fr/pasteur/ida/zellige/surfaceConstruction/element/os/OS.java b/src/main/java/fr/pasteur/ida/zellige/surfaceConstruction/element/os/OS.java
index 6834bcf39ce6fff33b3c0755c63abcb2f330e614..faa34402733831c20dd0d3169a6441ec1e9e1c32 100644
--- a/src/main/java/fr/pasteur/ida/zellige/surfaceConstruction/element/os/OS.java
+++ b/src/main/java/fr/pasteur/ida/zellige/surfaceConstruction/element/os/OS.java
@@ -11,6 +11,7 @@ import java.util.*;
 public class OS extends ArrayList< Coordinate >
 {
     private static TreeSet <Integer> list = new TreeSet<>();
+    private static TreeMap<Integer, Integer> occ = new TreeMap<>();
     private static int startingSize;
 
 
@@ -38,6 +39,8 @@ public class OS extends ArrayList< Coordinate >
     public void set( )
     {
         list.add( this.size() );
+        Integer j = occ.get(this.size() );
+        occ.put( this.size(), ( j == null ) ? 1 : j + 1 );
         /* Not necessary for the program.*/
         this.name = count;
         /*----------------*/
@@ -97,7 +100,6 @@ public class OS extends ArrayList< Coordinate >
         this.start = false;
     }
 
-
     /**
      * Sets the visited parameter to the specified value.
      *
@@ -153,7 +155,7 @@ public static void setStartingStatus(int dimension)
         startingSize = 0;
         if ( dimension == 0 )
         {
-                for ( int i = 0; list.size() > 10 && i <= list.size() / 4; i++ )
+                for ( int i = 0; list.size() > 20 && i <= list.size()/2 ;i++ )
             {
                 list.remove( list.last() );
             }
@@ -167,8 +169,12 @@ public static void setStartingStatus(int dimension)
         }
         startingSize = list.last();
         list = new TreeSet<>();
-    }
+    }}
 
+
+    public static void setStartingStatusStats(int dimension)
+    {
+            startingSize = list.last();
 }
 
 
@@ -181,4 +187,9 @@ public static void setStartingStatus(int dimension)
     {
         OS.count = count;
     }
+
+    public static TreeMap< Integer, Integer > getOcc()
+    {
+        return occ;
+    }
 }