diff --git a/daqviewer/tables.py b/daqviewer/tables.py
index 5b4cc53..ff21742 100644
--- a/daqviewer/tables.py
+++ b/daqviewer/tables.py
@@ -7,15 +7,22 @@ import dash_html_components as html
 import pandas as pd
 import numpy as np
 
-
 csv_name = os.path.dirname(__file__) + '../statistics.csv'
 df = pd.read_csv(csv_name)
 
 # Round floats
 df.iloc[:, 1:] = np.round(df.iloc[:, 1:] * 100) / 100
 
-var_list = ['H_sig', 'H_1%', 'H_max', 'Hm0', 'Tp', 'Tp1']
-df = df[['location'] + var_list]
+variables = {
+    'H_sig': 'o',
+    'H_1%': 'x',
+    'H_max': '□',
+    'Hm0': '◊',
+    'Tp': '',
+    'Tp1': '',
+}
+
+df = df[['location'] + list(variables.keys())]
 
 # add an id column and set it as the index
 # in this case the unique ID is just the country name, so we could have just
@@ -24,17 +31,15 @@ df = df[['location'] + var_list]
 df['id'] = df.index
 # df.set_index('id', inplace=True, drop=False)
 
-
 app = dash.Dash(__name__)
 
 app.layout = html.Div([
     dash_table.DataTable(
         id='datatable-row-ids',
-        columns=[
-            {'name': col, 'id': col} for col in df.columns
-            # omit the id column
-            if col != 'id'
-        ],
+        columns=[{
+            'name': [val, key],
+            'id': key
+        } for key, val in variables.items()],
         data=df.to_dict('records'),
         editable=True,
         filter_action="native",
@@ -49,11 +54,11 @@ app.layout = html.Div([
 ])
 
 
-@app.callback(
-    Output('datatable-row-ids-container', 'children'),
-    [Input('datatable-row-ids', 'derived_virtual_row_ids'),
-     Input('datatable-row-ids', 'selected_row_ids'),
-     Input('datatable-row-ids', 'active_cell')])
+@app.callback(Output('datatable-row-ids-container', 'children'), [
+    Input('datatable-row-ids', 'derived_virtual_row_ids'),
+    Input('datatable-row-ids', 'selected_row_ids'),
+    Input('datatable-row-ids', 'active_cell')
+])
 def update_graphs(row_ids, selected_row_ids, active_cell):
     # When the table is first rendered, `derived_virtual_data` and
     # `derived_virtual_selected_rows` will be `None`. This is due to an
@@ -75,31 +80,39 @@ def update_graphs(row_ids, selected_row_ids, active_cell):
 
     active_row_id = active_cell['row_id'] if active_cell else None
 
-    colors = ['#FF69B4' if id == active_row_id
-              else '#7FDBFF' if id in selected_id_set
-              else '#0074D9'
-              for id in row_ids]
+    colors = [
+        '#FF69B4' if id == active_row_id else
+        '#7FDBFF' if id in selected_id_set else '#0074D9' for id in row_ids
+    ]
 
     return [
         dcc.Graph(
             id=column + '--row-ids',
             figure={
-                'data': [
-                    {
-                        'x': dff['id'],
-                        'y': dff[column],
-                        'type': 'bar',
-                        'marker': {'color': colors},
-                    }
-                ],
+                'data': [{
+                    'x': dff['id'],
+                    'y': dff[column],
+                    'type': 'bar',
+                    'marker': {
+                        'color': colors
+                    },
+                }],
                 'layout': {
-                    'xaxis': {'automargin': True},
+                    'xaxis': {
+                        'automargin': True
+                    },
                     'yaxis': {
                         'automargin': True,
-                        'title': {'text': column}
+                        'title': {
+                            'text': column
+                        }
                     },
                     'height': 250,
-                    'margin': {'t': 10, 'l': 10, 'r': 10},
+                    'margin': {
+                        't': 10,
+                        'l': 10,
+                        'r': 10
+                    },
                 },
             },
         )
@@ -111,4 +124,4 @@ def update_graphs(row_ids, selected_row_ids, active_cell):
 
 
 if __name__ == '__main__':
-    app.run_server(debug=True)
+    app.run_server(debug=False)