Formulae Question

Hi,

I have on an Excel sheet listed out 3 randomly selected numbers 0, 1 and 2. Number 0 is listed in column A, number 1 listed in column B and 2 in column C. There are 5000 lines of these.

I am trying to come up with a method/forumlae to analyse out the largest, and average gap between a number not coming up.

For example, if 0 and 1 had come out for the last 10 times. How can I get excel to work out the largest gap where the number 2 had not appeared?

I am not sure if this can be done in excel so apologies if not,

Thank you,
Dave.