Just adding this because I forgot. Have Mint Proof sets starting with 1999 up to present date.
My mother started the mint proof statehood collection for all of us kids (even though we are all 38+). She turned them over to us several years back. This is what actually got me started collecting. I have been keeping the ball rolling and am getting them every year. My wife, went to an estate sale the other day and found a 1995 and 1979 Mint proof set all wrapped up nice and neat. I now have those too. Now I guess I need to go back and fill in the missing dates!!!! :) Bummer for me right!!