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This is a difficult question to answer with a high degree of accuracy, but could someone estimate to within an order of magnitude for me the chances of a zip code for a given address changing over the course of a year?
For example, would you say the chances of this are:
a) ~10%
b) ~1%
c) ~.1%
d) ~.01%
Just trying to get a rough sense of the constancy of these things for some code I'm writing. If the answer were ~10% I would proceed very differently than if it were ~.01%.
I maintain the Zip Code feature class for the USPS. Of our 34,000~ Zip Codes, I alter the boundaries of maybe 5~ a month.
Some Zip Codes contain thousands of addresses, some contain less than one hundred.
Hard to estimate an average yearly change per address, I would say .01%
Years ago I was advised to use census topology for thematic mapping rather than zip codes whenever possible. The reasoning was that zip codes are designed by the USPS for mail delivery purposes, not for our mapping purposes. Zip codes can be arbitrarily redrawn anytime. Post office boxes can have their own zip code which for mapping purposes is effectively a point inside another zip code. You could conceivably have things arranged so that commercial buildings have one zip code and residences have another, all in the same topological area.
