While going through two boxes this weekend, I came across a 2000 and a 2001 Kennedy half.. They both, (as well as a few 199xs) don't look the same as the older ones. The portrait looks like is is a bit smaller than on the old ones. Is this normal? I can't say I've seen any halves from 2000 onwards, and they do look different.. But it might just be me.
It's very possible, they've been constantly making changes to the kennedy halves. Somewhere around 1992 they made changes to the hair, etc. There are smalls changes every few years.
Yes. It perfectly normal for the Kennedy P_ortrait to have reduced in size from its initial release. Lower relief was the targeted goal. Notice the distance between the tip of the bust and the date. As the years have gone by, that distance has gotten greater. Another "low relief" addition was the "spaghetti Hair". I do not have absolute design dates but what you see above can be used as a guidline.