diff --git a/gtsam/base/Vector.h b/gtsam/base/Vector.h
index ed90a7126..9567d9980 100644
--- a/gtsam/base/Vector.h
+++ b/gtsam/base/Vector.h
@@ -60,6 +60,7 @@ GTSAM_MAKE_VECTOR_DEFS(9);
 GTSAM_MAKE_VECTOR_DEFS(10);
 GTSAM_MAKE_VECTOR_DEFS(11);
 GTSAM_MAKE_VECTOR_DEFS(12);
+GTSAM_MAKE_VECTOR_DEFS(15);
 
 typedef Eigen::VectorBlock<Vector> SubVector;
 typedef Eigen::VectorBlock<const Vector> ConstSubVector;