I find applying market cap thinking and principals helpful to individual cards of large populations, to better inform investment decisions at specific grades and where those grades sit as a percentage of total pop. I’ve done this recently for the ‘52 Topps Mantle using VCP sales data and all grading pops for each grade. The results are quite fascinating.
The below is an interesting resource I found on the subject of card market cap:
Where a Sports Card Market Cap Falls Short
While market cap is a useful tool, it’s not without limitations. Here are a few key drawbacks:
Assumes Every Card Will Sell for the Most Recent Price
Market cap relies on the last sale price, which may not reflect what all copies would sell for if they hit the market simultaneously. This makes it a theoretical measure rather than a literal one.
Sports Cards Are Illiquid and Have Information Asymmetry
Unlike financial markets, the sports card market is illiquid and often filled with inaccurate data. If the input data is unreliable, the market cap calculation becomes less trustworthy.
Ignores Demand Beyond Price
Market cap doesn’t account for:
How frequently a card is bought or sold.
How many copies are available for sale (float).
Tracking recent sales or active listings can complement the market cap for a fuller picture.
Assumes All Copies Are in Circulation
Many cards have been cracked and resubmitted or crossed to other grading companies, inflating population counts and skewing market cap calculations.
https://www.thesmartercollector.com/...ard-market-cap