Understanding the Registry Set Coin Rating system / rating multiplier - Morgans
Although I started collecting MANY years ago, I only started aggressively about 2 years ago, and have been focusing on silver dollars with PCGS certs. Now that I am nearing the end of my Basic set, I am starting to analyze the coins, values, and ratings within the set.
I don't completely understand the multiplier being used to rate the coins within the set. I know common dates get a rating equal to the grade. AN MS64 gets a rating of 64. HOWEVER, lower population coins get higher ratings correct? If so, can some one explain this: EX 1 - 1893 s in F15. It was a bear to find it. We all know that coin as the king. It rates at a 150. That is the max, 10x Multiplier. Great. EX 2 - 1881 s MS 64 - po of over 30K coins. Rating 64. 1X multiplier rating. Perfect.
EX 3 - Now I look at an 1886 o AU 53. There are literally a dozen PCGS certified in AU53 on e-bay at any given time. It gets an 8X multiplier with over 6200 population graded higher. That seems super high. EX 4 - Last - 1900 P MS 66 - total pop higher 321. 2x multiplier. Strange right??
The math does not make sense to me. Can you help me understand the correlation between population, and rating multiplier? Is it grade specific as well as overall population sensitive? Are there other factors? Thank you!!! Rich
Comments
I have not read any details describing any formula for the weightings based on population higher. There also seems to be some subjectivity in the numbers for weightings in general, some of which may be related to price, mintages, coin availability, etc.
There have been several sets where I have asked the set registry in an email to take a look at weightings and update them if needed. You could provide them with the outliers you believe are there described above, and they will see if some should be revised when they get a chance.
My US Mint Commemorative Medal Set
I understand what you are writing about and can give two possible explanations as to why certain coins are valued certain ways.
The first is simply an error in judgement given to the weight of a specific issue within PCGS. That error might be how PCGS interprets the overall value/rarity of a coin or might be a typo or keystroke error that was never fixed.
The second is a bit more complex and looks at each coin along a sliding scale of grades within the context of PCGS parameters. Those parameters, by definition, include a single multiplier value per coin (from one through ten) in integer format that is used no matter what the grade is for the coin. That is, a coin might be quite common, like the 1881-S, and so receives a multiplier of X1 and no one has an issue with it. Conversely, a coin might be the king or quite scarce all along the grading spectrum, like the 1893-S, and so receives a multiplier of X10 and no one has an issue with it.
Then there are the tweeners. The 1886-O has a very large original mintage, but they were generally produced quite poorly and it is thought that a considerable number of these coins were placed into circulation at the time of issue and then perhaps more than half the mintage was melted during the 1918 Pittman Act. This leads to the coin being relatively available in circulated grades and then getting pricey as it approaches MS. The poor quality characteristics of the initial mintage makes higher end MS coins exceptionally scarce and valuable. This leaves PCGS in kind of a bind with respect to their parameters of giving a single multiplier value per issue. Should they give the coin a multiplier reflective of initial production or estimated survivorship? Should they base their multiplier upon population and value of non-MS coins? Or should they use the extreme scarcity and high value of MS pieces to dictate the multiplier? In this case, I believe PCGS went heavily with the latter when they came up with their multiplier of X8.
If the registry has various multipliers for any given coin based upon the grade of the coin that would make the registry far more accurate in terms of placing sets where they should be relative to one another. However, at least at this time we have not seen PCGS make that commitment to this feature for the public.
In honor of the memory of Cpl. Michael E. Thompson
TomB, fantastic answer. Thank you!!!!