diff --git a/README.md b/README.md
index 66c89fd..1bdcbe3 100644
--- a/README.md
+++ b/README.md
@@ -24,6 +24,9 @@ Those can be installed using pip and the _requirements.txt_ file provided with t
 
 ## Versions
 
+* v1.3.1
+ - support dates without day (YYYY-mm)
+
 * v1.3
   - jogobot module not longer included
 * v1.2
@@ -40,4 +43,4 @@ Those can be installed using pip and the _requirements.txt_ file provided with t
 GPLv3+
 
 ## Author Information
-Copyright 2018 Jonathan Golder <jonathan@golderweb.de>
+Copyright 2021 Jonathan Golder <jonathan@golderweb.de>
diff --git a/charts.py b/charts.py
index 69f0afa..9016c2b 100644
--- a/charts.py
+++ b/charts.py
@@ -11,7 +11,7 @@
 #
 #  modified by:
 #
-#  Copyright 2017 Jonathan Golder <jonathan@golderweb.de>
+#  Copyright 2021 Jonathan Golder <jonathan@golderweb.de>
 #
 #  This program is free software; you can redistribute it and/or modify
 #  it under the terms of the GNU General Public License as published by
diff --git a/countrylist.py b/countrylist.py
index 3298f68..606b8df 100644
--- a/countrylist.py
+++ b/countrylist.py
@@ -239,8 +239,11 @@ class CountryList():
                                     int( self._chartein_raw ) ).monday() )
         # Complete date string present
         else:
-            self.chartein = datetime.strptime( self._chartein_raw,
+            try:
+                self.chartein = datetime.strptime( self._chartein_raw,
                                                "%Y-%m-%d" )
+            except ValueError:
+                self.chartein = datetime.strptime( self._chartein_raw, "%Y-%m" )
 
     def get_chartein_value( self ):
         """