I am a supporter ofSt. Joseph's hospice. If you find this site useful or if it helped you, consider a small donation toSt. Joseph's, please. Information onSt. Joseph's  "Probable impossibilities are to be preferred to improbable possibilities." [Aristotle] Here I present some functions for random number generation. I assume that Excel's © internal rand() function generates random numbers of sufficient quality (that is: randomness). You may want to substitute it. In this case search the web for alternatives. Random functions: Examples of simple distribution functions are presented here. Cholesky - Generate correlated random numbers with a Cholesky decomposition. Iman Conover - Generate correlated random numbers with worksheet functions or with VBA. sbGrowthSeries - Generate a random data series with a given compoundgrowth rate and a given maximum relative change rate per step PF_Allocate - Generate portfolio assets with a given sum and lower boundaries and upper boundaries Random_Pick - Pick n random cells from selection RndDecPlace - Create a random number between two borders with a given number of decimal places. sbExactRandHistogram - Create a random distribution with exactly the requested frequency for given numbers (Largest Remainder method will be applied if that is not exactly possible to minimize the absolute error) sbRandInt - Generate n non-repeating (or repeating up to r times) random integers between two given borders sbRandIntFixSum creates random integers which add up to a defined sum sbRandSum1 - Generate n random numbers which sum up to 1 UniqRandInt - Generate n unique random integer numbers in a given range 1..m (m >= n) [provided just for historical purposes - I suggest to use sbRandInt now]