diff --git a/galsec.py b/galsec.py
index be54f1d..f236c6d 100644
--- a/galsec.py
+++ b/galsec.py
@@ -333,8 +333,8 @@ class Galsec:
         """
         for fluid in self.fluids:
             x_bin = np.trunc(self.data[fluid]["position"][:, 0] / delta_x)
-            y_bin = np.trunc(self.data[fluid]["position"][:, 0] / delta_y)
-            z_bin = np.trunc(self.data[fluid]["position"][:, 0] / delta_z)
+            y_bin = np.trunc(self.data[fluid]["position"][:, 1] / delta_y)
+            z_bin = np.trunc(self.data[fluid]["position"][:, 2] / delta_z)
             self.data[fluid]["x_bin"] = x_bin
             self.data[fluid]["y_bin"] = y_bin
             self.data[fluid]["z_bin"] = z_bin