diff --git a/buildstock_query/tools/upgrades_visualizer/viz_data.py b/buildstock_query/tools/upgrades_visualizer/viz_data.py
index db0b175..c0854cb 100644
--- a/buildstock_query/tools/upgrades_visualizer/viz_data.py
+++ b/buildstock_query/tools/upgrades_visualizer/viz_data.py
@@ -154,7 +154,7 @@ def init_monthly_results(self, metadata_df):
             run_obj.save_cache()
             monthly_df = pl.from_pandas(monthly_vals, include_index=True)
             monthly_df = monthly_df.with_columns(pl.col('time').dt.month().alias("month"))
-            monthly_df = monthly_df.with_columns(pl.col('month').map_dict(num2month).alias("month"))
+            monthly_df = monthly_df.with_columns(pl.col('month').replace(num2month).alias("month"))
             modified_cols = []
             for col in ts_cols:
                 # scale values down to per building and convert to m_btu to match with annual results