Maps updates and accuracy

ericfeunekes This isn't something that would typically be documented and is completely dependent on the type of data you are looking for. Entities that have well known boundaries, such as counties and states, will have very high accuracy. Where as entities that don't have well known boundaries, such as zip codes, will have a degree of error that would vary with every zip code and is basically unknown exactly (if it was known, there wouldn't be a margin of error).

Zip codes are points, and don't have officially defined polygon areas, and there is a lot of spaces that don't have addresses (i.e. back country of a national parks), so every data provider has to make some assumptions to create logical areas which are then used to power a reverse geocoder. To complicate things further some zip codes represent PO, boxes and several of them can be located at the same location within another zip code. There is even one zip code in the US that moves around (its a boat on the Detroit river, zip code 48222: https://en.wikipedia.org/wiki/J._W._Westcott_II)