Index: examples/wflow_rhine_sbm/wflow_sbm.ini
===================================================================
diff -u -ra625823533647abcecdab68adc8b1991b1d63a51 -r9fb69bd394b86a7a17e668f72567e692f141e911
--- examples/wflow_rhine_sbm/wflow_sbm.ini	(.../wflow_sbm.ini)	(revision a625823533647abcecdab68adc8b1991b1d63a51)
+++ examples/wflow_rhine_sbm/wflow_sbm.ini	(.../wflow_sbm.ini)	(revision 9fb69bd394b86a7a17e668f72567e692f141e911)
@@ -119,8 +119,12 @@
 self.PotenEvap=PET
 self.Precipitation=P
 self.MassBalKinWave=wat
-self.SurfaceRunoff_mean_10=m30
+self.SurfaceRunoff_mean_15=m30
 
+# self.VAriable=nr_of_points_to_average
+[rollingmean]
+self.SurfaceRunoff=15
+
 [summary]
 self.MaxLeakage=MaxLeakage.map
 #self.CCup=CCup.map
Index: wflow-py/wflow/wf_DynamicFramework.py
===================================================================
diff -u -ra625823533647abcecdab68adc8b1991b1d63a51 -r9fb69bd394b86a7a17e668f72567e692f141e911
--- wflow-py/wflow/wf_DynamicFramework.py	(.../wf_DynamicFramework.py)	(revision a625823533647abcecdab68adc8b1991b1d63a51)
+++ wflow-py/wflow/wf_DynamicFramework.py	(.../wf_DynamicFramework.py)	(revision 9fb69bd394b86a7a17e668f72567e692f141e911)
@@ -240,16 +240,14 @@
         :param name:
         :return:
         """
-
-
         if self.count[name] == 0:
             self.result[name] = data
         else:
             if self.mode[name] =='mean':
-                self.result[name] -= self.result[name]/self.points[name]
-                self.result[name] += data/self.points[name]
+                self.result[name] = self.result[name] * (self.points[name] -1)/self.points[name] + data/self.points[name]
 
         self.count[name] = self.count[name] + 1
+
         return self.result[name]
 
 class wf_sumavg():
@@ -1056,7 +1054,16 @@
         # Add the on-lien statistics
         self.onlinestat = wf_online_stats()
 
-        self.onlinestat.addstat('SurfaceRunoff',points=10)
+        rollingvars = configsection(self._userModel().config, "rollingmean")
+        for thisvar in rollingvars:
+            try:
+                thisvarnoself = thisvar.split('self.')[1]
+            except:
+                logging.error("Entry in ini invalid: " + thisvar)
+                raise ValueError
+            pts = int(self._userModel().config.get("rollingmean", thisvar))
+            self.onlinestat.addstat(thisvarnoself,points=pts)
+
         # Fill the summary (stat) list from the ini file
         self.statslst = []
         _type = wf_sumavg(None)
@@ -2042,16 +2049,18 @@
                 self._decrementIndentLevel()
                 # Save state variables in memory
                 self.wf_QuickSuspend()
-                self.wf_savedynMaps()
-                self.wf_saveTimeSeries()
+
                 for a in range(0, len(self.statslst)):
                     data = getattr(self._userModel(), self.statslst[a].varname)
                     self.statslst[a].add_one(data)
 
                 for key in self.onlinestat.statvarname:
-                    stvar = self.onlinestat.getstat(getattr(self._userModel(),key),key)
+                    #stvar = self.onlinestat.getstat(getattr(self._userModel(),key),key)
+                    stvar = self.onlinestat.getstat(cover(self.DT.currentTimeStep * 1.0), key)
                     setattr(self._userModel(),self.onlinestat.statvarname[key],stvar)
 
+                self.wf_savedynMaps()
+                self.wf_saveTimeSeries()
 
             #self.currentdatetime = self.currentdatetime + dt.timedelta(seconds=self._userModel().timestepsecs)