Update app.py

app.py

@@ -52,7 +52,7 @@ whisper_df = pd.read_csv(whisper_csv_results)
 def formatter(x):
     if type(x) is str:
         x = x
-    elif x == None:
+    elif x == -1:
         x = "NA"
     else: 
         x = round(x, 2)