diff --git a/toargridding/grids.py b/toargridding/grids.py
index a0d7325535c96a1639834d43eb9adfe737e5104f..47477f22927a520c7a0b1b9a99d071522edc0876 100644
--- a/toargridding/grids.py
+++ b/toargridding/grids.py
@@ -98,8 +98,10 @@ class RegularGrid(GridDefinition):
 
     def group_data_by_cell(self, data: pd.DataFrame, coords: pd.DataFrame):
         cell_indices = self.as_cell_index(coords)
+
+        # will convert cell_indices to float as some nans ar present
         data_with_indices = data.join(
-            cell_indices.to_frame(GridDefinition.cell_index_name), how="inner"
+            cell_indices.to_frame(GridDefinition.cell_index_name), how="outer"
         )
 
         return data_with_indices.groupby(GridDefinition.cell_index_name)
@@ -134,8 +136,6 @@ class RegularGrid(GridDefinition):
         values = self.create_gridded_statistics(time, grouped_timeseries)
         metadata = get_variable_attributes(cell_statistic)
 
-        print(cell_statistic)
-
         gridded_ds = gridded_ds.assign(  # maybe better all in one ? (memory)
             {cell_statistic: (["latitude", "longitude", "time"], values)}
         )
@@ -146,7 +146,7 @@ class RegularGrid(GridDefinition):
         values = np.empty((self.lat.size, self.lon.size, time.size))
         values[...] = self.fill_value
 
-        index = self._as_xy_index[grouped_timeseries.index]
+        index = self._as_xy_index[grouped_timeseries.index.astype(int)]
         values[index.T[0], index.T[1]] = grouped_timeseries.values.reshape(
             -1, time.size
         )