I have a distribution of numbers (population totals) across 295 zip codes. I
would like to identify the zip code total that represents the "80/20" break
(the pareto principle - the assumption that 20% of the number zip codes
contain 80% of the population of the region).

I.e., I would like to enter a function that returns the zip code total that,
above which, the zip code totals comprise 80% of the population. This will
enable me to identify the number of zip codes that comprise 80% of the
population, comparitively small, with a COUNTIF function.

Is this possible.

Thanks,

DEI