diff --git a/_delphi_utils_python/delphi_utils/export.py b/_delphi_utils_python/delphi_utils/export.py
index f62a1afcf..9b35ccb26 100644
--- a/_delphi_utils_python/delphi_utils/export.py
+++ b/_delphi_utils_python/delphi_utils/export.py
@@ -70,6 +70,9 @@ def create_export_csv(
         even if there is no data for the day. If false, only the days present are written.
     logger: Optional[logging.Logger]
         Pass a logger object here to log information about contradictory missing codes.
+    weekly_dates: Optional[bool]
+        Whether the output data are weekly or not. If True, will prefix files with
+        "weekly_YYYYWW" where WW is the epiweek instead of the usual YYYYMMDD for daily files.
 
     Returns
     ---------