I think all two or three of Us have been using the wrong terms, maybe its just me, my thinking has been corrected but not quenched as to a researching for the answer; as to the correct use to a "Coating" not insulation that is put on a wire when manufactured. That is just put on to protect it from corrosion. Maybe I'm just flat out wrong!
I tried researching the FPN as listed under table 8. I also tried to search the other numbers listed with-in. It's not light reading and not to say direct to the point of the OP. I didn't dig deep, I'm sure the definitions are in there, but I gave up.
I did go to
Southwire and found there general sudo vague, one might even consider it quite finite, "Wire and Cable Terms/Rating" page.
Take a look at CONDUCTOR INSULATION / CABLE JACKETS, one might come to the same conclusion as previously stated.