I am trying to compare the average for the first nine months of 2007, to
2006; once october is over this will change to the first 10 months of 2007
and so on. I have an automated cell that counts the number of months that
have passed in 2007, and another that takes the average of the the 2007
results. The problem is that I need to automate a cell to average the first 9
months of 2006, and then automatically change to 10 months and then to 11
months as time passes. I'm looking for a function that is something like:
average first 9 values, so I can input a range of values and then a formula
that will determine how many of those values to average. Does anyone know how
I can accomplish this? If my explanation isn't clear, please let me know.

Thanks.