diff --git a/webviz_subsurface/plugins/_rft_plotter/_views/_sim_vs_obs_view/_utils/_crossplot_figure.py b/webviz_subsurface/plugins/_rft_plotter/_views/_sim_vs_obs_view/_utils/_crossplot_figure.py
index 85d29e21c..fbcd0795a 100644
--- a/webviz_subsurface/plugins/_rft_plotter/_views/_sim_vs_obs_view/_utils/_crossplot_figure.py
+++ b/webviz_subsurface/plugins/_rft_plotter/_views/_sim_vs_obs_view/_utils/_crossplot_figure.py
@@ -17,7 +17,10 @@ def update_crossplot(
 
     for _ens, ensdf in df.groupby("ENSEMBLE"):
         dframe = (
-            ensdf.groupby(["WELL", "DATE", "ZONE", "TVD"]).mean().reset_index().copy()
+            ensdf.groupby(["WELL", "DATE", "ZONE", "TVD"])
+            .mean(numeric_only=True)
+            .reset_index()
+            .copy()
         )
         trace = {
             "x": dframe["OBSERVED"],