Let $L \in \mathbb{R}(s)$ be a proper scalar loop transfer function, and set $S=(1+L)^{-1}$. Assume that $S$ is stable, that neither $L$ nor $1+L$ has zeros or poles on the imaginary axis, that there are no unstable pole-zero cancellations in the formation of $L$, and that $L(s)=O(1/s)$ as $|s|\to\infty$ in the closed right half-plane. Let $\mathcal P_+$ be the multiset of poles $p$ of $L$ with $\operatorname{Re}(p)>0$. Then \begin{align*} \int_0^\infty \log |S(i\omega)|\,d\omega = \pi \sum_{p \in \mathcal P_+} \operatorname{Re}(p). \end{align*}