  For $d\ge 3$ we first show that the Hausdorff dimension of the set of
$A$-divergent on average points in the $(d-1)$-dimensional closed horosphere in
the space of $d$-dimensional Euclidean lattices, where $A$ is the group of
positive diagonal matrices, is at most $\frac{d-1}{2}$. In particular, this
upper bound is sharp for $d=3$.
  We apply this to compute the Hausdorff dimension of the set of exceptions to
the inhomogeneous uniform version of Littlewood conjecture. We say that a pair
$(\xi_1,\xi_2)\in\mathbb{R}^2$ satisfies the inhomogeneous Littlewood
conjecture if
$$\liminf_{q\to\infty}q\|q\xi_1-\theta_1\|_{\mathbb{Z}}\|q\xi_2-\theta_2\|_{\mathbb{Z}}=0$$
for all $(\theta_1,\theta_2)\in\mathbb{R}^2$, where $\|\cdot\|_\mathbb{Z}$
denotes the distance to the nearest integer. We prove that the Hausdorff
dimension of the set of pairs $(\xi_1,\xi_2)\in\mathbb{R}^2$ not satisfying the
inhomogeneous Littlewood conjecture is $1$, which is equal to the Hausdorff
dimension of the conjectural set of exceptions.
