numismaster.com / By Paul M. Green / January 22, 2013
It may be a long time before we really figure out just how available the 1964-D Kennedy half dollar is in top grades. We start with the basic fact that the demand for the 1964-D Kennedy half dollar was extraordinary. The nation was still trying to recover from the killing of the President, and as part of that process everyone seemed to need the new Kennedy half dollars.
The mintages of the first 1964 Kennedy half dollars were enormous. The 1964-D had a total mintage of 156,205,466. That would have been a record were it not for the 1964 mintage from Philadelphia, which was even higher.
In addition to a high mintage, there was very heavy saving. People wanted multiple examples, and large numbers were put away in 1964. Additional numbers were put away for safekeeping in 1965 when the amount of silver was reduced in the half dollar to 40 percent.