Don't agree with your scheme. Things are a lot more complex. Just for numbers sake .de domain has nearly as twice of the number of domainnames registered than net. Als co.uk is bigger than net. Also orgs can fetch enormous prices, because non-profit organization have enormous budgets through funding, and want the org extension.
It's rather complex to come to a good appriasal.
My expectation is that net will decline in the next 10 years or so. This because net is what I would call the in between extension. You have a company but your name is taken in the com extension so you take net. And people that are on a net site will in a lot of cases also move to the com just out of curiosity.
Especially in Europe you see companies will take a name domain if their name is taken as com, or just because they identify them with the country. For that reason US will also become more popular in the future.
Actually snoop, you're right. I lost all the data long ago, so I only go by memory. HOWEVER, this data dated back before the .us, etc. were made. So the data might be a bit obsolete now. I'm just making a logical guess based on the stats that were established pre .us.
And zapper8, valuation doesn't come specifically by how many registrations an extention has. It's how well-known/established a domain extention is. Who know? .de might become far more established on the WWW this time in 5 years. sex.de just might overpower sex.com. One never knows.