Hello
I wonder if you could establish a formula for the number of new addresses by day.
Using the blockchain, you can find the number of new addresses each day in the past from the beginning of bitcoin (in january 2009, I think).
You can also find the number of total addresses used in summing the previous ones.
This could give you the opportunity to find out a formula (probably exponential) that gives you the total number of addresses for each day in the past.
So in extrapolating, this formula to the future, and using your formula for the bitcoin price, you could estimate the price for each day in the  future.
What do you think ? Could you do that or is it impossible ?

Please fit us a function for the price dependent on time
   P(t) = function (time-offset)
Thanks.