Kailee and Sandon,
Thank you both for the information. I wasn't asking specifically about the coin, just showing what I have. I did use the wrong terminology..my bad, as I did know it's a strike error. I guess my question is more this. Doubling is shown for some years (like the 51S, but not 52D) on the variety plus page. Is it specific to that year or does it cross years? If it doesn't cross years then what makes it a variety on one year but not the other?
Someone, somewhere, makes that distinction and I guess I'll try to find the references online that Kailee gave.
My apologies if it seems like a mundane question, but I tend to overthink things sometimes and should look at my coins, make notes about any doubling or errors and move on.
Again, thank you for your time.
Chuck