diff --git a/plot_transmission_timeline.py b/plot_transmission_timeline.py
index 7dc5cc5..cb0aaea 100755
--- a/plot_transmission_timeline.py
+++ b/plot_transmission_timeline.py
@@ -190,14 +190,12 @@ if __name__ == "__main__":
 
     plt.clf()
 
+    print("Calculate and polt CDF...")
     # Get the frequency, PDF and CDF for each value in the series
 
     # Frequency
-    transmission_df \
-        .groupby("goodput")["goodput"] \
-        .agg("count") \
-        .pipe(pd.DataFrame) \
-        .rename(columns={"goodput": 'frequency'}, inplace=True)
+    transmission_df.groupby("goodput")["goodput"].agg("count").pipe(pd.DataFrame)
+    transmission_df.rename(columns={"goodput": 'frequency'}, inplace=True)
 
     # PDF
     transmission_df['pdf'] = transmission_df['frequency'] / sum(transmission_df['frequency'])