quantum mechanics - What is expectation values of this anti-commutator $langle { Delta hat x,Delta hat p} rangle~?$

What is expectation values of this anti-commutator $\langle \{ \Delta \hat x,\Delta \hat p\} \rangle~?$

where the $\Delta \hat p=\hat p-\langle \hat p \rangle$ and $\hat p$ is momentum operator and so $\Delta \hat x=\hat x-\langle \hat x \rangle$ and $\hat x$ is position operator operator.