diff --git a/causalml/metrics/visualize.py b/causalml/metrics/visualize.py
index a2923a09..8dd62d08 100644
--- a/causalml/metrics/visualize.py
+++ b/causalml/metrics/visualize.py
@@ -113,11 +113,17 @@ def get_cumlift(
             sorted_df["cumsum_tr"] = sorted_df[treatment_col].cumsum()
             sorted_df["cumsum_ct"] = sorted_df.index.values - sorted_df["cumsum_tr"]
             sorted_df["cumsum_y_tr"] = (
-                sorted_df[outcome_col] * sorted_df[treatment_col]
-            ).fillna(0).cumsum(skipna=True).astype(float)
+                (sorted_df[outcome_col] * sorted_df[treatment_col])
+                .fillna(0)
+                .cumsum(skipna=True)
+                .astype(float)
+            )
             sorted_df["cumsum_y_ct"] = (
-                sorted_df[outcome_col] * (1 - sorted_df[treatment_col])
-            ).fillna(0).cumsum(skipna=True).astype(float)
+               (sorted_df[outcome_col] * (1 - sorted_df[treatment_col]))
+                .fillna(0)
+                .cumsum(skipna=True)
+                .astype(float)
+            )
 
             lift.append(
                 sorted_df["cumsum_y_tr"] / sorted_df["cumsum_tr"]