fix rounding

app.py

@@ -133,7 +133,8 @@ original_df.sort_values(by='Common Voice', inplace=True)
 
 # Compute delta between average WER and CV WER
 original_df['Detla Avg. C.V. WER'] = original_df['Average WER ⬇️'] - original_df['Common Voice WER ⬇️']
-original_df['Detla Avg. C.V. WER'] = original_df['Detla Avg. C.V. WER'].apply(formatter)
+original_df['Detla Avg. C.V. WER'] = pd.to_numeric(original_df['Detla Avg. C.V. WER'], errors='coerce') # Convert to numerical data type
+original_df['Detla Avg. C.V. WER'] = original_df[col].apply(lambda x: round(x, 2) if not pd.isna(x) else '') # Round and handle NaN values
 
 COLS = [c.name for c in fields(AutoEvalColumn)]
 TYPES = [c.type for c in fields(AutoEvalColumn)]