Jaime Hernandez:
The 1981-P Kennedy Half Dollar appears to be an average issue as the mintage is about 30 million. Other dates in the series have mintages well over a hundred million, like the 1971-P with a mintage over 300 million. While other more recent dates have mintages under 2 million, such as the 2010 - 2012 issues which have mintages of 1.7 million.
The 1981-P Kennedy Half Dollar seems to be well struck and examples in circulated condition up to about MS65 condition are fairly common. In MS66 they begin to be scarce with possibly several thousand examples still out there. In MS67 condition or higher they are very scarce and possibly no more than a couple hundred examples exist.