If I have a note worth $10.00 in grade 63, is there a formula or rule of thumb to figure what the price would be for a 64, 65, 66, etc.?
Not really a rule of thumb, one year may have 5000 graded above 63, and for the next year a 63 could be a top pop. There would be a value difference between the two. It's best to go by completed auctions for an idea of price.
"Back in the day" for coin collecting there was such a formula. It is the basis of the 70 point grading scale. A VG10 was worth $10, and a XF45 was worth $45. Every time you quote a number grade you are referencing such a grade/pricing system. Nowadays with massively overhyped "grade rarity" crud it no longer applies, but it used to.
I don't know for sure...but that doesn't seem right. The Sheldon grading scale isn't that old and when they started grading coins in this manner...many rarities were know. I refuse to believe that a 1909 Lincoln Cent and a 1909-S VDB Lincoln Cent were both $10 coins in VG10 "back in the day."
No sir, my point was if a coin was a $10 coin in VG, it was a $45 coin in XF. Its scalable, if its a $4500 coin in XF, it was a $1000 coin in VG. Sorry for the confusing post. Bottom line, a XF45 was worth 4.5 times more than a VG10, that is how these grades GOT their number designations.
The price depends on population - not necessarily by type, but also by distribution between grades. Suppose we have a certain coin. 100 examples are known. 99 of those are VG, and 1 is XF. That XF coin would not be worth 4.5 times as much as the VG. It would be worth far, far more, due to low supply. Collectors seeking the best quality examples they can find/afford will be willing to pay far more for the highest quality example, even if that's only an XF. On the other hand, if from that same 100 coin population, 1 of the coins was VG and the 99 were XF, the XF coins would not be worth 4.5 times as the VG. In fact, HA.com and Lyn Knight have put up interesting estimates for XF/AU notes. Those estimates were higher than the CU notes of the same issue, simply citing the fact that there were so many CU notes on the market and few circulated examples. I didn't follow the listings close enough to see where they closed at.
It's how Sheldon created the number designations, yes, but it didn't really work even back then. As Funkee points out, some coins (and notes) are usually found in high grade and others are usually found in low grade, so the ratio of high-grade value to low-grade value isn't going to be the same from one coin/note to the next. Sheldon's multipliers sort of worked for the majority of large cent varieties, but there were plenty of exceptions even in that limited universe, let alone now when the Sheldon scale has been appropriated to grade enormously diverse numismatic items that Sheldon never heard of.
Thank You all for your input. I wasn't sure how to fill in the blanks on grade 66 and higher on my 2 paper money programs. Estimated values only go to 65. I guess I'll just average recent sales and go from there.
