I'm trying to figure out what this really illustrates. If you were to put 1924-D on the graph, I imagine it would spike even higher than the 14-D. That the 09-S VDB has a relatively flat curve could mean a couple things. It could mean the both the pricing and populations are flat across all grades, but you'd see the same for a 74-D (until you got into ultra-grades). Perhaps what you want to show is what the price multiplied by the population, with the sum of the products over all grades indicating what the total demand (covetedness) is for the date. This puts the 09-S VDB far ahead of the 14-D.