Why Do Graded Coin Values Mostly Seem To Decrease In Value Over Time?

I would say, maybe, they were popular in those grades. Maybe not, idk, I know that there are limited early slabs like, Maya Angelou MS69 and Sally Ride MS69 that fetched decent auction prices. Also in lower grades certain mint marks that had top pop fetched decent auctions. I guess we both can find examples to prove a point. I buy coins without early designations, I just see future value in the early slabs simply because of the cutoff dates. It is fairly new to this market and I expect some push back for sure. I could be way off, but something needs to intrigue newcomers.

Please provide your evidence for this statement.
(As a work colleague used to say ... "In God we trust. All others provide data.")

Maybe I am missing something, but if I go to the PCGS site, here is the graph I see for the PCGS 3000 index in the last 3 years:


If we look at longer term data, the trend changes.
Please let us know what data you are working from.

I guess I brought up the topic because almost every coin I ever looked up values on were trending down. I don't know if there is exact data to support what I am saying for the entire market, it is bits of evidence, kind of like polling to get a gist of what's going on. I am not knocking PCGS or faulting them for the falling prices, I know Auctions often determine values.

I have learned a lot on here, though I don't always agree, I certainly appreciate everyone who took the time to discuss this topic.

i agree with CarrsCoins. its all about supply and demand just like any other commodity. there are two types of collectors. one are collectors and the other are investors or a combination of the two. if you're a collector you are buying coins to fill a hole in your collection most of which are common. with the decline in generational interest common coins are going to be common coins pretty much forever and the prices will reflect that. rarer coins are going to be purchased more so by investors. folks that may be collectors but purchase these coins to increase in value over time. rarer coins in higher grades are always going to be in demand, however, prices of these can exceed what they typical collector can pay so this limits demand and in turn holds down the prices. however, if you look at the prices of lets say MS65 morgans you will see that that over the last couple years they have increased considerably but when you get to that level and prices investors want to ensure that the coin itself is in fact that grade so they for the most part avoid buying them raw and you can see this in demand for slabbed high grade coins.

bottom line...if you want to see increases in values in your coins over time buy high grade slabbed rarer coins.

what constitutes rare and high grade is relative.

for early copper (and many other coins) rarity is discusses using R#s.

R-8 is 1-3 copies known.
R-7 is 4-12.
R-6 is 13-30.
R-5 is 31-75.
R-4 is 76-200,
R-3 is 201-600
R-2 is 601-2,000
R-1 is more than 2,000

coins that many people consider rare like the 1916-D dime or the 1909-S vdb cent would be listed as R-1 in this scale and labeled as common. their supply is outstripped by the massive demand for those coins. they demand a significant premium.

on the flip side there are quite a few large cent variations that are R-4 and R-5 and carry no significant premium. there arent 200 people collecting them by variety. there is more supply than demand even though they are quite a bit rarer than those 20th century key dates. if 500 people start seriously collecting large cents by variety all of the R-3 coins start commanding premiums. if half the current sets are sold and nobody replaces that demand then some of R-6 coins wont be much more expensive than common coins.

condition can be relative too. my avatar picture is of an 1800 Half Dime. it is a unique die combination (the LM-5 die marriage) and the only known version of that coin. its worn slick and has a hole in it. it is the finest known example of that coin. its also the worst known. it takes one coin surfacing for that coin to no longer be top pop.

I am not sure how far away you are from the border with New Hampshire, but it might be worthwhile for you to check out the New Hampshire Coin & Currency Expo, https://nhcoinexpo.com/
Next one is April 7-8, 2023.

And here is the one from 1970.



Had you bought in 1970, you would be doing ok. However, had you bought in 1989 you would be totally underwater.

Certified coins of the same grade can be of varying quality. Many of today's collectors want coins that are solid or premium quality for their assigned grade and CAC will verify previously graded coins to be a solid/high quality example for that grade. There are many coins that are certified accurately for their grade. Unfortunately, it is an inescapable reality that many are at the lower end of the quality range for the assigned grade. CAC's rejection of a coin does not necessarily mean that CAC believes the coin has been over-graded. It simply means that there are other coins with CAC stickers that are of higher quality for the grade. CAC will eventually reject tens of thousands of accurately graded coins. The CAC green sticker also adds to the value and demand. And now they are doing their own full grading in slabs.

@NumisEd Yes that info would be helpful if someone perhaps is collecting quite a large batch of those classic coins that make up the index which I posted a link to earlier. Otherwise I guess you can visit specific price changes (for PCGS coins only) over time by cllicking the price changes link. I mentioned one for quarters earlier but below is where to find it on a PCGS price page. A person who mainly was buying say modern top pop coins and holding for example wouldnt get much data out of that index and further may have done poorly investment wise since those are among the coins that have the biggest chance to drop quite alot over time.