Base Set Bill #91: PSA 9 vs PSA 10
Base Set Bill #91 shows a modest premium between PSA 9 and PSA 10: a $42 dollar gap, with the gem mint multiplier at 1.8x. Based on the most recent PSA 10 sale of $100.00 on Apr 7, 2026, the math leans toward holding the 9: expected value turns negative at conservative upgrade probabilities once the resub fee is in.
PSA 10
$91.80
Last sale $100.00 on
PSA 9
$50.00
Last sale $45.56 on
PSA 8
$29.99
Last sale $29.99 on
The Spread
The PSA 9 to PSA 10 spread on Bill #91 Base Set.
$42
Dollar gap, PSA 9 to PSA 10
1.8x
PSA 10 sells for 1.8x a PSA 9
Three-Outcome EV Calculator
15%
70%
15%
Defaults are conservative starting points. Adjust based on the specific slab. A borderline 9 with strong centering plays differently than a 9 with edge wear.
PSA 10 outcome (sale price minus resub minus acquisition)
$0
PSA 9 outcome (regrade, no upgrade)
$0
PSA 8 outcome (downgrade, slower sell, tied capital)
$0
Expected Value
$0
Math favors holding the 9
Where this card lands in the broader Base Set picture: a non-holo with a $42 gap between PSA 9 and PSA 10. The PSA 9 to PSA 10 jump on WOTC-era cards reflects population scarcity at the top grade, not raw print run.
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