Just looking at the PSA population report for a particular set will only tell you so much. The main thing you’ll know at a glance is which cards in the set are the hardest to grade relative to the other cards in the set.
Let’s compare PSA population reports for a few different cards -
1st edition Charizard (Base Set):
PSA 10: 120 (5.1%)
PSA 9: 632 (26.7%)
PSA 8: 484 (20.4%)
PSA 7: 304 (12.8%)
PSA 1-6: 830 (35.1%)
Total: 2,368
1st edition Chansey (Base Set):
PSA 10: 46 (4.5%)
PSA 9: 343 (33.8%)
PSA 8: 275 (27.1%)
PSA 7: 130 (12.8%)
PSA 1-6: 223 (21.2%)
Total: 1,015
1st edition Fighting Energy (Base Set):
PSA 10: 472 (49.5%)
PSA 9: 398 (41.8%)
PSA 8: 58 (6.1%)
PSA 7: 6 (0.6%)
PSA 1-6: 19 (2.0%)
Total: 953
1st edition Ampharos (Neo Genesis):
PSA 10: 155 (28.5%)
PSA 9: 279 (51.3%)
PSA 8: 59 (10.8%)
PSA 7: 26 (4.8%)
PSA 1-6: 25 (4.6%)
Total: 544
1st edition Slowking (Neo Genesis):
PSA 10: 10 (1.8%)
PSA 9: 186 (32.7%)
PSA 8: 257 (45.2%)
PSA 7: 83 (14.6%)
PSA 1-6: 33 (5.8%)
Total: 569
1st edition Fighting Energy (Neo Genesis):
PSA 10: 9 (50.0%)
PSA 9: 8 (44.4%)
PSA 8: 1 (5.6%)
PSA 7: 0 (0.0%)
PSA 1-6: 0 (0.0%)
Total: 18
So, what kinds of conclusions can we extract from this data? Among other things:
* Given that the same number of Chanseys and Charizards were produced and 2.3x as many Charizards were submitted to PSA, people were more likely to think that any 1st edition Charizard should be submitted to PSA (the gap has actually narrowed in recent years with the rise of prices in general, back in the day many people would only have seen the Charizard as worthy of submitting to PSA).
* Given that people have more selectively sent Chanseys to PSA compared to Charizards and there is still a lower % of pop 10s, Chansey is likely significantly harder to grade as a 10.
* In Neo Genesis there is an even greater disparity between the easiest-to-grade and hardest-to-grade cards. Ampharos and Slowking have almost the same number of submissions but Slowking is 16x harder to grade as a 10 compared to Ampharos (some of this may have to do with PSA 9 Slowkings being re-submitted to PSA, but the relatively even total population between the two cards shows that for the most part people are probably just submitting once).
* The PSA 10 pop of a 1st edition Fighting Energy (Neo Genesis) is even lower than a 1st edition Slowking. Why is that? Well, the obvious conclusion is that because people don’t think the card is worth grading. This tells you that *almost* no one is actually trying to collect a complete set of PSA 10 1st edition Neo Genesis (which given the population of the rarest holos makes perfect sense). In contrast, it is clear that more people see value in grading literally ANY mint 1st edition base set card.
But there’s still more that’s not being seen… and for that you would really need to understand a couple of things that don’t show up in the data. Namely, how rare is the sealed product for the set? How expensive is the sealed product and how frequently is it being opened? And what are the historical trends in population growth? All of these questions must be considered because the data doesn’t exist in a vacuum.
Let’s consider simply the last question I asked - how much have the populations of various cards been growing?
Well, here’s how much a few of the cards I mentioned have seen their populations increase since December 2018:
PSA 10 1st edition Charizard (Base Set): +1
PSA 10 1st edition Chansey (Base Set): +0
PSA 10 1st edition Fighting Energy (Base Set): +64
PSA 10 1st edition Ampharos (Neo Genesis): +35
PSA 10 1st edition Slowking (Neo Genesis): +2
PSA 10 1st edition Fighting Energy (Neo Genesis): +1
(This data comes from pokemonprice.com. See the tab at the top of efour. They have data going back to 2017.)
So what does this tell me?
* The fact that almost no new Charizards and Chanseys have graded as a 10 in the last couple of years tell me that any population of ungraded mint copies of these cards has already been drained and that the sealed product is far too expensive for anyone to open.
* The population increase in the Ampharos tells me that in the last couple of years more people have recognized the value of mint 1st edition Neo Genesis cards. More people now recognize that any mint WOTC 1st edition holo is worth getting professionally graded.
* The Fighting Energy population increase for Base Set vs Neo Genesis continues to tell the story that people see any mint 1st edition Base Set card as worthy of grading, but very few people see 1st edition Neo Genesis the same way.
Generally speaking, you’ll notice that population growth staggers to a halt once the raw mint copies have been drained out of the population the and price of sealed product becomes too expensive to open.
Of course, there is yet another factor if a set has little population growth - people simply don’t care about a set. If cards from a random 2012 set aren’t seeing a big increase in the PSA population, it may simply be because no one cares. That’s why you’ll also want to check the price of the sealed product and see the quantity of sealed product being sold.