Addition of new geography type in the predefined Geography structure

Content

Hi All,

We are using India Geography with structure as country-->State-->City-->Town-->Pin code. Now we want to add a new geography type Zone in the predefined structure (country-->zone-->state-->city-->Town-->Pin code)..We also want to have this zone to be tagged to each location, so on manage location page, we want to have this field of zone.Also Employees to see it when they add address in Self-Service.

Is it feasible? If yes, how can we configure it and what would be the impact on existing location or employee data.

Priyanka