diff --git a/R/read_daily_data_over_shape.R b/R/read_daily_data_over_shape.R
index 6f80e9e6..da65d46b 100644
--- a/R/read_daily_data_over_shape.R
+++ b/R/read_daily_data_over_shape.R
@@ -97,11 +97,14 @@ get_daily_data_from_grid_files <- function(grid_files, shape, scale)
   # Mask the full grid over Germany with the shape and crop the grid
   grids <- mask_and_crop_grids(grids, shape)
 
-  # Calculate statistics, considering the conversion factor "scale"
-  data <- do.call(rbind, lapply(grids, raster_stats, scale = scale))
+  # Calculate statistics, considering the scaling factor, add metadata
+  cbind(metadata, summarise_over_all_grids(grids, scale))
+}
 
-  # Add metadata
-  cbind(metadata, data)
+# summarise_over_all_grids -----------------------------------------------------
+summarise_over_all_grids <- function(grids, scale)
+{
+  do.call(rbind, lapply(grids, raster_stats, scale = scale))
 }
 
 # extract_metadata_from_files_daily --------------------------------------------
diff --git a/R/read_monthly_data_over_shape.R b/R/read_monthly_data_over_shape.R
index 84a9581e..a5d9ff88 100644
--- a/R/read_monthly_data_over_shape.R
+++ b/R/read_monthly_data_over_shape.R
@@ -64,12 +64,9 @@ read_monthly_data_over_shape <- function(
     grids <- mask_and_crop_grids(grids, shape)
   }
 
-  # Calculate statistics, considering the conversion factor "scale"
-  data <- do.call(rbind, lapply(grids, raster_stats, scale = scale))
-
   # Provide file metadata (file, year, month)
   metadata <- extract_metadata_from_files_monthly(files = grid_files)
 
-  # Add metadata
-  cbind(metadata, data)
+  # Calculate statistics, considering the scaling factor, add metadata
+  cbind(metadata, summarise_over_all_grids(grids, scale))
 }