Don't remember exactly, but seems like I received about 30-40 mint primary hundos back when they first became available (out of 300-400 total). So I'd guess about 10%, although my mint hundos were sold long ago.
FWIW, the chip in your pic does not look mint. Mine were flawless, unmarked, sharp-edged, and still chalky.
You are right Dave, I just took it out of the airtite and it is in excellent+. Not nearly as sharp as the rack I have up in the classifieds right now, plus it has marks. However, the point was that the LCV's are super rare in top condition. Were all 40 of yours LCV? If so, that is awesome!!