diff --git a/annofabcli/__version__.py b/annofabcli/__version__.py
index e5102d30..35424e87 100644
--- a/annofabcli/__version__.py
+++ b/annofabcli/__version__.py
@@ -1 +1 @@
-__version__ = '1.9.0'
+__version__ = '1.9.1'
diff --git a/annofabcli/statistics/__init__.py b/annofabcli/statistics/__init__.py
new file mode 100644
index 00000000..e69de29b