diff --git a/plot_transmission_timeline.py b/plot_transmission_timeline.py
index cb0aaea..528b5c1 100755
--- a/plot_transmission_timeline.py
+++ b/plot_transmission_timeline.py
@@ -194,14 +194,14 @@ if __name__ == "__main__":
     # Get the frequency, PDF and CDF for each value in the series
 
     # Frequency
-    transmission_df.groupby("goodput")["goodput"].agg("count").pipe(pd.DataFrame)
-    transmission_df.rename(columns={"goodput": 'frequency'}, inplace=True)
+    transmission_df["gp_frequency"] = transmission_df["goodput"]
+    transmission_df.groupby("gp_frequency")["gp_frequency"].agg("count").pipe(pd.DataFrame)
 
     # PDF
-    transmission_df['pdf'] = transmission_df['frequency'] / sum(transmission_df['frequency'])
+    transmission_df["pdf"] = transmission_df["gp_frequency"] / sum(transmission_df["gp_frequency"])
 
     # CDF
-    transmission_df['cdf'] = transmission_df['pdf'].cumsum()
+    transmission_df["cdf"] = transmission_df["pdf"].cumsum()
     transmission_df.reset_index(inplace=True)
 
     transmission_df.plot(x="goodput", y=["cdf"], grid=True)