Could anyone please provide me with the formula of the cumulative distribution function of the stock price (geometric brownian motion)? So that one could calculate the probability that the stock price rises by more than 20% in 1 year, given 30% volatility and 10% drift, for example.I have only found the probability density function at
http://www.sitmo.com/eq/157, but I need a CDF, and also the PDF formula seems to be giving incorrect results (or maybe I just made a mistake).VBA / C++ code of the CDF / PDF would also be great.