diff --git a/grum/mainwin.py b/grum/mainwin.py
index c38f9a9..48b8217 100644
--- a/grum/mainwin.py
+++ b/grum/mainwin.py
@@ -134,7 +134,7 @@ class MainWindow(QMainWindow):
         data = {}
         for name, item in self.lst.items.items():
             desc = item.value
-            data[name] = dict(xs=desc.xs, ys=desc.ys)
+            data[name] = {k: v for k, v in desc.__dict__.items() if not k.startswith("_") and v is not None}
 
         write_dict(fn, data)