diff --git a/reports/heatmap.ipynb b/reports/annual_category_location_heatmap.ipynb
similarity index 66%
rename from reports/heatmap.ipynb
rename to reports/annual_category_location_heatmap.ipynb
index 4460000..7c9a219 100644
--- a/reports/heatmap.ipynb
+++ b/reports/annual_category_location_heatmap.ipynb
@@ -26,8 +26,11 @@
     "# Species category to report on\n",
     "category = \"\"\n",
     "\n",
-    "# Export format - either PNG or PDF\n",
-    "export_format = \"PNG\""
+    "# Export format for the heatmap chart:\n",
+    "# PNG     - export as PNG image\n",
+    "# PDF     - export as PDF file\n",
+    "# <blank> - do not export\n",
+    "export_format = \"\""
    ]
   },
   {
@@ -65,7 +68,12 @@
     "# Connect to the database, execute the query and read the results into a dataframe\n",
     "database_path = os.environ[\"NATURE_RECORDER_DB\"]\n",
     "connection = sqlite3.connect(database_path)\n",
-    "df = pd.read_sql_query(query, connection, parse_dates=[\"Date\"])"
+    "df = pd.read_sql_query(query, connection, parse_dates=[\"Date\"])\n",
+    "\n",
+    "# Check there is some data\n",
+    "if not df.shape[0]:\n",
+    "    message = f\"No data found for category '{category}' at location '{location}' during '{year}'\"\n",
+    "    raise ValueError(message)"
    ]
   },
   {
@@ -76,11 +84,38 @@
    "outputs": [],
    "source": [
     "import calendar\n",
+    "import re\n",
+    "\n",
+    "# Create the folder to hold exported reports\n",
+    "export_folder_path = Path(\"exported\")\n",
+    "export_folder_path.mkdir(parents=True, exist_ok=True)\n",
     "\n",
     "# Pre-process the data to provide a heatmap data source\n",
     "df[\"Month\"] = df[\"Date\"].dt.month\n",
-    "heatmap_data = df.groupby([\"Species\", \"Month\"]).size().unstack(fill_value=0)\n",
-    "heatmap_data.columns = [calendar.month_abbr[m] for m in heatmap_data.columns]"
+    "heatmap_data = df.groupby([\"Species\", \"Month\"])[\"Count\"].sum().unstack(fill_value=0)\n",
+    "\n",
+    "# Make sure all months are represented even if there are no sightings in the data set for that month\n",
+    "for month in range(1, 13):\n",
+    "    if month not in heatmap_data.columns:\n",
+    "        heatmap_data[month] = 0\n",
+    "\n",
+    "# Re-order the columns in calendar order\n",
+    "heatmap_data = heatmap_data[sorted(heatmap_data.columns)]\n",
+    "\n",
+    "# Set the labels to the month abbreviations rather than month numbers\n",
+    "heatmap_data.columns = [calendar.month_abbr[m] for m in heatmap_data.columns]\n",
+    "\n",
+    "# Export the heatmap data to Excel\n",
+    "clean_location = re.sub(\"[^0-9a-zA-Z\\-]+\", \"\", location.replace(\" \", \"-\"))\n",
+    "export_file_path = export_folder_path / f\"{year}-{category}-{clean_location}-Heatmap.xlsx\"\n",
+    "heatmap_data.to_excel(export_file_path.absolute(), sheet_name=\"Sightings\")\n",
+    "\n",
+    "# Print the heatmap data\n",
+    "with pd.option_context('display.max_rows', None,\n",
+    "                       'display.max_columns', None,\n",
+    "                       'display.precision', 3,\n",
+    "                       ):\n",
+    "    display(heatmap_data)"
    ]
   },
   {
@@ -94,24 +129,20 @@
     "import matplotlib.pyplot as plt\n",
     "\n",
     "# Generate the heatmap\n",
-    "plt.figure(figsize=(12, 24))\n",
+    "plt.figure(figsize=(12, heatmap_data.shape[0] / 3))\n",
     "sns.heatmap(heatmap_data, cmap=\"YlOrRd\", annot=False)\n",
     "plt.title(f\"Number of Sightings of {category} at {location} in {year}\")\n",
     "plt.xlabel(\"\")\n",
     "plt.ylabel(\"\")\n",
     "\n",
-    "# Create the folder to hold exported reports\n",
-    "export_folder_path = Path(\"exported\")\n",
-    "export_folder_path.mkdir(parents=True, exist_ok=True)\n",
-    "\n",
     "# Export to PNG\n",
     "if export_format.casefold() == \"png\":\n",
-    "    export_file_path = export_folder_path / f\"{year}-{category}-Heatmap.png\"\n",
+    "    export_file_path = export_folder_path / f\"{year}-{category}-{clean_location}-Heatmap.png\"\n",
     "    plt.savefig(export_file_path.absolute(), format=\"png\", dpi=300, bbox_inches=\"tight\")\n",
     "\n",
     "# Export to PDF\n",
     "if export_format.casefold() == \"pdf\":\n",
-    "    export_file_path = Path(\"exported\") / f\"{year}-{category}-Heatmap.pdf\"\n",
+    "    export_file_path = export_folder_path / f\"{year}-{category}-{clean_location}-Heatmap.pdf\"\n",
     "    plt.savefig(export_file_path.absolute(), format=\"pdf\", bbox_inches=\"tight\")\n",
     "\n",
     "# And show the plot\n",
@@ -121,7 +152,7 @@
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "venv",
+   "display_name": "Python 3",
    "language": "python",
    "name": "python3"
   },
diff --git a/reports/requirements.txt b/reports/requirements.txt
index 6d6825a..fa8ba65 100644
--- a/reports/requirements.txt
+++ b/reports/requirements.txt
@@ -18,6 +18,7 @@ cycler==0.12.1
 debugpy==1.8.14
 decorator==5.2.1
 defusedxml==0.7.1
+et_xmlfile==2.0.0
 executing==2.2.0
 fastjsonschema==2.21.1
 fonttools==4.57.0
@@ -61,6 +62,7 @@ nest-asyncio==1.6.0
 notebook==7.4.0
 notebook_shim==0.2.4
 numpy==2.2.4
+openpyxl==3.1.5
 overrides==7.7.0
 packaging==24.2
 pandas==2.2.3
diff --git a/reports/sql/sightings.sql b/reports/sql/sightings.sql
index 7f22c56..da1f68d 100644
--- a/reports/sql/sightings.sql
+++ b/reports/sql/sightings.sql
@@ -1,4 +1,4 @@
-SELECT l.Name AS 'Location', sp.Name AS 'Species', sp.Name AS 'Category', DATE( s.Date ) AS 'Date'
+SELECT l.Name AS 'Location', sp.Name AS 'Species', sp.Name AS 'Category', DATE( s.Date ) AS 'Date', IFNULL( s.Number, 1 ) AS 'Count'
 FROM SIGHTINGS s
 INNER JOIN SPECIES sp ON sp.Id = s.SpeciesId
 INNER JOIN CATEGORIES c ON c.Id = sp.CategoryId
@@ -6,4 +6,4 @@ INNER JOIN LOCATIONS l ON l.Id = s.LocationId
 WHERE l.Name = '$LOCATION'
 AND s.Date LIKE '$YEAR-%'
 AND sp.Name LIKE '%$SPECIES%'
-AND c.Name = "$CATEGORY";
\ No newline at end of file
+AND c.Name = "$CATEGORY";