FWIW, here's an image of one of the tools from Hoadley that draws probability bands/cones. It's not the most beautiful thing in the world, but it has more inputs than some I've seen. I guessed at some parameters for the S%P 500 - 1850, 1.5% dividend yield and 14% annualized volatility.

rmejia 

This could be it:

Hi, i am trying to adapt this code but no success, can u help me? I want starting point to be custom date, is it possible ?
Thank you!

alchemist74 

Hi, i am trying to adapt this code but no success, can u help me? I want starting point to be custom date, is it possible ? Thank you!

Sorry @alchemist74 i'm not using TOS anymore, I've left the platform for another and haven't looked at this code since starting this thread. What I would do is make the input both a start and end date and then run the calculation off that. That would allow you to adjust it easily.

TOS does a probability of expiring cone study that you may be interested in.
It would probably do something similar to what you are looking for. I can't load TOS right now so I can't see exactly what it is called.

"Probability of Expiring Cone"

I'd post a picture but can't figure out how/if I can upload one here.