What is the mean of $\operatorname{sinc}(t)$ (cardinal sine)?

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Can the mean of $\operatorname{sinc}(t)=\frac{\sin(t)}{t}$ be calculated over the entire $t$ domain, i.e., $$\int_{a}^{b}\frac{\operatorname{sinc}(t)}{b-a}dt,\text{ where } a=-\infty, \ b=\infty?$$ Can the calculation be approximated somehow using limits? I have a feeling the mean exists by just looking at a graph the function. The function itself isn't defined at $t=0$, therefore the definition $$\operatorname{sinc}(t)=\begin{cases}1,&\quad t=0,\\\frac{\sin(t)}{t},&\quad \mathrm{otherwise},\end{cases}$$ is used.

Can the calculation be split into two or three sections?

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The Dirichlet integral is

$$\int_0^{+\infty} \frac{\sin(x)}{x}dx=\frac{\pi}{2}$$

$\implies$

$$\lim_{(a,b)\to(-\infty,+\infty)}\int_a^b\frac{\sin(x)}{x}dx=\pi$$

$\implies$

$$\lim_{(a,b)\to (-\infty,+\infty)}\frac{1}{b-a}\int_a^b \frac{ \sin(x)}{x}dx=0.$$