Stränga postnummer i Alaska?

Maponics som tillhandahåller data för många kartläggningsverktyg, verkar vara källan till detta - för som de anger i dokumentationen:

ZIP Codes

This product includes the names and boundaries (and other attributes as Maponics may choose to provide) for postal ZIP Codes in the United States. Maponics’ proprietary process builds these polygons using multiple data sources. The ZIP Code boundaries are based off of the carrier route boundaries, using a combine/dissolve/extend approach. Because there are cases where carrier routes do not exist, the ZIP Code boundaries have been extended using a proprietary process so that ZIP Codes cover the entire US. However, there are intentional holes in the ZIP Code layer for major water and landmark areas. In all cases where carrier routes exist, the ZIP Codes share the border line with carrier routes.

There are some areas where there is not sufficient data to create ZIP Code polygons. Where possible, Maponics has created temporary ZIP Code areas and given the area a ZIP Code starting with the three digit ZIP Code followed by either an “MH” or “MX” (ex. 901MH) to differentiate area encompassed by water (“MH” ) or land (“MX”). Other such areas appear as holes. Some unique ZIP Codes might appear as polygons (for example, a university).

Zip-koder tilldelades inte dessa områden. När det behövs kommer MX att ersättas med siffror när postnummeret tilldelas för en del av "fyllnadsområdet". Se till exempel 99691 inom området 996MX.

Alaska är enormt och mycket glesbefolket. Ingen anledning att allokera postnummer för områden där ingen kommer att skicka ett mail.