You don't really have to track it. Just set a google calendar event for 10 years from now, and look back at the stock history then.
If somehow google services go away and you don't get that event reminder, the question may be moot by then... not really, but an interesting thought anyways.
> Exxon's better reflect the value of the underlying assets.
That's like valuing a car based on the price of the steel it contains instead of where it can take you.