diff --git a/climetlab/utils/patterns.py b/climetlab/utils/patterns.py
index 3727338f..8fad3099 100644
--- a/climetlab/utils/patterns.py
+++ b/climetlab/utils/patterns.py
@@ -88,7 +88,7 @@ def substitute(self, value, name):
         return self.format % value
 
 
-TYPES = {"": Any, "int": Int, "float": Float, "date": Datetime, "enum": Enum}
+TYPES = {"": Any, "int": Int, "float": Float, "date": Datetime, "strftime": Datetime, "enum": Enum}
 
 
 class Constant: