Excel Random Number Function

Excel has a random number generator, that returns uniformly distributed random numbers between 0 and 1. Like many of Excel's statistical functions the one in Excel 2003 is better than the earlier ones. This is an important reason to upgrade to at least Excel 2003. The functions in Excel 2007 do not appear to be different or improved.

The Excel random number generator is easy to use it takes no arguments and is just the function: Rand(). Note even though there are no parameters the () are required. Below is a snippet of spreadsheet that generates 6 random numbers. Each time the spreadsheet is

recalculated the random numbers change. The spreadsheet Example Distributions.xls gives some results of using Rand(). Table I below shows the results of 10,000 calls to Rand() in terms of a Chi-Square test.

They do appear to be uniformly distribution, and well within the critical Chi-Square values. VBA the language FinPak is written also has a random number function and this is used internally by the functions when a random number is required but not supplied by the user.