Long before the advent of grading services numismatists were keeping track of coin populations. Perhaps a decade ago, I wrote an article suggesting that grading service population reports were probably the most important commercially orientated numismatic references ever published. I will stick by this claim. The various reports showing grading service activity provide important information to those who understand the limitations of this data.
Several months ago, I sent examples of the highest graded coins done by one grading service to another who then crossed these pieces over by giving them the same grade. This resulted in these three coins now being listed as among the finest known with two grading services. Three coins had become six. Instead of being a responsible grading service participant, I didn't bother to send the holder labels back to the first grading service so they could remove these coins from their population records. My neglect has created a permanent flaw that will appear in every subsequent population report issued by this company.
I also plead guilty to having removed coins from grading service holders prior to selling them. That I didn't report this activity to the grading service means their population figures will always remain inflated.
I'm quite certain none of the grading services expected the population information they publish would remain entirely accurate nor is this information presented as such in the reports. At best, the grading service data serves as a useful guide. This is especially true when considering the scarcity of a particular issue based on the entire graded population. In many cases population data has confirmed the relative scarcity of some coins. In other cases, numismatists have been surprised to learn that certain coins are indeed far scarcer or more common that was previously thought.
As might be expected, certain individuals have figured out ways to use population reports as powerful marketing tools. By far, the commonest practice is to "fabricate" rarities by submitting high grade common coins for grading. Most numismatists would consider it silly, if not absurd, to spend even $10 to have a coin that might be worth $1 graded by a grading service. This is not the case with those who market common coins with low grading service populations as scarce or even rare items. Certainly the people selling this "stuff" don't bother to tell their investor-type clients that the real reason a grading service has seen so few of a certain coin is because very few people would be foolish enough to waste the money to have the item graded. Some, if not many may disagree, but it does seem some grading services have decided to validate the supposed "rarity" of certain common coins by refusing to give many of these pieces a MS-69 or MS-70 grade even when the coin has no perceptible flaws. Simply put, with this common material the grading service stands to benefit from an increased number of submissions by arbitrarily limiting the number of pieces that are given the ultimate grades.
The population data for a particular coin may be inflated in a certain grade due to the scarcity and value of this coin in the next highest grade. Only because quite current information is available to me, I've used the NGC grading service population for the 1948 Canadian dollar to illustrate my point. According to information obtained on 3/30/03, NGC has graded 22 examples of the 1948 dollar as MS-62. In all grades, this is the most plentiful population. At a glance, one might make the incorrect assumption that most 1948 dollars sent to grading services will receive a grade of MS-62. I would suggest this population figure is considerably inflated due to coins once graded MS-62 being removed from the holder and submitted again in hopes of receiving the MS-63 grade. The same could be said for the population of MS-63 1948 dollars. Certainly some of the coins once graded as MS-63 were removed from the holder and submitted again in hopes of receiving a MS-64. When this didn't happen the result was to inflate the population of coins graded as MS-63.
To someone who collects Victoria large cents in Very Fine condition all of this talk about grading services and their activities may seem like a complicated game. It is. The important thing is to recognize the shortcomings while using the good information population reports provide to your advantage.