diff --git a/src/lib/aqdiagram/data/floatingavg.c b/src/lib/aqdiagram/data/floatingavg.c
index 8cefae4..f8d4f11 100644
--- a/src/lib/aqdiagram/data/floatingavg.c
+++ b/src/lib/aqdiagram/data/floatingavg.c
@@ -13,6 +13,9 @@
 #include "./floatingavg.h"
 
 
+static double _averageOverArray(const double *lastValues, int num);
+
+
 
 AQDG_GRAPH_DATAPAIR_LIST *AQDG_Data_FloatingAverage(const AQDG_GRAPH_DATAPAIR_LIST *dpList, int num)
 {
@@ -28,36 +31,19 @@ AQDG_GRAPH_DATAPAIR_LIST *AQDG_Data_FloatingAverage(const AQDG_GRAPH_DATAPAIR_LI
     while(dp) {
       AQDG_GRAPH_DATAPAIR *newDp;
       double v;
-      int i;
 
       v=AQDG_Graph_DataPair_GetValueY(dp);
-      if (idx>=num)
-        idx=0;
-      lastValues[idx]=v;
-      idx++;
+      idx%=num;
+      lastValues[idx++]=v;
       cnt++;
 
       if (cnt<num) {
         /* buffer not full, average over the values we already have */
-        if (cnt) {
-          double totalSum=0.0;
-
-          for (i=0; i<cnt; i++) {
-            totalSum+=lastValues[i];
-          }
-          v=totalSum/((double)cnt);
-        }
-        else
-          v=0.0;
+        v=_averageOverArray(lastValues, cnt);
       }
       else {
-        double totalSum=0.0;
-
         /* buffer full, average over full buffer */
-        for (i=0; i<num; i++) {
-          totalSum+=lastValues[i];
-        }
-        v=totalSum/((double)num);
+        v=_averageOverArray(lastValues, num);
       }
 
       newDp=AQDG_Graph_DataPair_dup(dp);
@@ -73,3 +59,23 @@ AQDG_GRAPH_DATAPAIR_LIST *AQDG_Data_FloatingAverage(const AQDG_GRAPH_DATAPAIR_LI
 
 
 
+double _averageOverArray(const double *lastValues, int num)
+{
+  double v=0.0;
+
+  if (num) {
+    double totalSum=0.0;
+    int i;
+
+    /* average over full buffer */
+    for (i=0; i<num; i++) {
+      totalSum+=lastValues[i];
+    }
+    v=totalSum/((double)num);
+  }
+  return v;
+}
+
+
+
+