diff --git a/parso/cache.py b/parso/cache.py
index 2c6493e..0165398 100644
--- a/parso/cache.py
+++ b/parso/cache.py
@@ -18,7 +18,7 @@ from parso._compatibility import FileNotFoundError
 LOG = logging.getLogger(__name__)
 
 
-_PICKLE_VERSION = 30
+_PICKLE_VERSION = 31
 """
 Version number (integer) for file system cache.