diff --git a/src/ssb_konjunk/statbank_format.py b/src/ssb_konjunk/statbank_format.py
index 777f0c0..964f3e1 100644
--- a/src/ssb_konjunk/statbank_format.py
+++ b/src/ssb_konjunk/statbank_format.py
@@ -2,7 +2,11 @@
 
 
 def format_time_period(
-    df: pd.DataFrame, year: int, quarter: int | str = "", col_name: str = "periode", month: int | str = ""
+    df: pd.DataFrame,
+    year: int,
+    quarter: int | str = "",
+    col_name: str = "periode",
+    month: int | str = "",
 ) -> pd.DataFrame:
     """Add column with time period.