Where can I find the mesonic decay constants in the particle data group listings? I can't seem to find the mesonic decay constants in any of the relevant particle data group (PDG) listings. I'm specifically looking for the neutral Kaon decay constants.

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*Link to the PDG interactive guide
For example, where can I find the standard pion decay constant $f_{\pi}\approx 130\,\textrm{MeV}$ (or with a different convention, differing by a factor of $\sqrt{2}$, $f_{\pi}\approx 93\,\textrm{MeV}$)?
 A: With the help of @Slereah, I found the PDG article regarding the mesonic decay constant.


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*Leptonic Decays of Charged Pseudoscalar Mesons
In that document, you can find a summary of all the known mesonic decay constants. However, you may need to dig a bit, because they also explain all the nuances of deducing those values.
For example, it should be noted that, what is experimentally observable are not directly the decay constants $f_P$, but the products $|V_{q_1q_2\in P}|f_P$ and separately $|V_{q_1q_2\in P}|$, where $|V_{q_1q_2\in P}|$ is the modulus of the $(q_1,q_2)$ CKM matrix element, where $q_1$ and $q_2$ are the flavors of the valence quarks in the pseudoscalar meson $P$. Therefore, one experimentally extracts the value $f_P$ by dividing:
$$\frac{|V_{q_1q_2\in P}|f_P}{|V_{q_1q_2\in P}|}$$
Theoretical calculations, with input of some other mesonic numbers such as the pion mass or pion decay constant, can directly calculate $f_P$. It is important to mention this because the CKM matrix element $|V_{us}|$ has an inconsistent value between different experiments (see details on page 14 of the paper linked above), and therefore the authors refuse to explicitly quote the value of $f_{K+}$! (the $K^+$-meson is comprised of up and strange quarks) From page 14:

"We do not quote an “experimental” value for the kaon decay constant
  because the value of $|V_{us}|$ is less clear
  given the $∼2\sigma$ tension between the values of $|V_{us}|$ obtained
  from leptonic and semileptonic kaon decays."

