Fix wrong name

wsgi.py

@@ -156,9 +156,9 @@ def plot(
     # Convert plot to SVG image
     imgdata = io.StringIO()
     fig.savefig(imgdata, format="svg")
-    svgImage.seek(0)  # rewind the data
+    imgdata.seek(0)  # rewind the data
 
-    return svgImage.read()
+    return imgdata.read()
 
 
 @app.route("/")
@@ -188,6 +188,7 @@ def tables(
 
             tfoot = [
                 "  <tfoot>",
+                "    <tr>",
                 "      <td>Gesamt</td>",
             ]
             for i in range(len(df.columns) - 2):