diff --git a/visualizer/parameters.py b/visualizer/parameters.py
index 353d7fd0c4668799bf44e522e526f79a1bb83e64..dd104812412310be8e60b6424bc7fef18c0d2dd3 100644
--- a/visualizer/parameters.py
+++ b/visualizer/parameters.py
@@ -31,6 +31,6 @@ def year_type(s):
     """Type converter for valid years."""
     if s.isdigit():
         val = int(s)
-        if val in range(10000):
+        if val in range(1, 10000):
             return val
     raise ValueError(f'bad year arg: {s!r}')