diff --git a/src/robofish/evaluate/evaluate.py b/src/robofish/evaluate/evaluate.py
index a9c92e64f404c577eca0dd24cb536532575b8c81..2596b22182dbf072e5f68ebba6b978f30afc6e2d 100644
--- a/src/robofish/evaluate/evaluate.py
+++ b/src/robofish/evaluate/evaluate.py
@@ -100,6 +100,7 @@ def evaluate_speed(
         list(speeds),
         bins=20,
         label=labels,
+        density=True,
         range=[min(left_quantiles), max(right_quantiles)],
     )
     plt.title("Agent speeds")