diff --git a/04-One-Dimensional-Kalman-Filters.ipynb b/04-One-Dimensional-Kalman-Filters.ipynb
index 6ab7705..4086be2 100644
--- a/04-One-Dimensional-Kalman-Filters.ipynb
+++ b/04-One-Dimensional-Kalman-Filters.ipynb
@@ -1290,7 +1290,7 @@
     }
    ],
    "source": [
-    "book_plots.plot_errorbars([(160, 8, 'A'), (170, 8, 'B')], xlims=(150, 180))"
+    "book_plots.plot_errorbars([(160, 3, 'A'), (170, 9, 'B')], xlims=(150, 180))"
    ]
   },
   {