diff --git a/src/ParamOutputImpl/Plot/HistoPlot/Histo2DFunction.cc b/src/ParamOutputImpl/Plot/HistoPlot/Histo2DFunction.cc
index ae700bd..6bd0f10 100644
--- a/src/ParamOutputImpl/Plot/HistoPlot/Histo2DFunction.cc
+++ b/src/ParamOutputImpl/Plot/HistoPlot/Histo2DFunction.cc
@@ -132,11 +132,25 @@ void Mean2DFunction::apply(MatrixGrid &matrixGrid, double* xData, double* yData,
 	allValues = getMatrixValues(xData,yData,zData,nbData,xRange,yRange,xBinNumber,yBinNumber);
 
 	for (unsigned int i(0); i < matrixGrid.size(); ++i){
+        double mean = NAN;
+        if (!allValues[i].empty()) {
+            int nb = 0;
+            for (std::vector<double>::iterator it = allValues[i].begin(); it != allValues[i].end(); ++it){
+                if (std::isfinite(*it) && !std::isnan(*it)) {
+                    if (std::isnan(mean)) {
+                        mean = 0;
+                    }
+                    mean += *it;
+                    nb++;
+                }
+            }
+            if (nb > 0) {
+                mean /= nb;
+            }
+        }        
+		matrixGrid[i].value = mean;
 
-		double sum = std::accumulate(allValues[i].begin(), allValues[i].end(), 0);
-		matrixGrid[i].value=sum/allValues[i].size();
-		
-		if(zMax < matrixGrid[i].value)
+        if(zMax < matrixGrid[i].value)
 			zMax = matrixGrid[i].value;
 		if(zMin > matrixGrid[i].value)
 			zMin = matrixGrid[i].value;
diff --git a/test/plots_ref/centos-7/TmaAmda/ReLease5/Histo2D/plot_histo2d_06_REF.png b/test/plots_ref/centos-7/TmaAmda/ReLease5/Histo2D/plot_histo2d_06_REF.png
index 9918e76..5536373 100644
Binary files a/test/plots_ref/centos-7/TmaAmda/ReLease5/Histo2D/plot_histo2d_06_REF.png and b/test/plots_ref/centos-7/TmaAmda/ReLease5/Histo2D/plot_histo2d_06_REF.png differ
--
libgit2 0.21.2