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Geography Technical Documentation

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Geography Technical Documentation

Every survey, and program has technical documentation to assist users with the published data, maps and files.

File Naming Conventions

Here you will find file naming convention for various files types.
Record Layouts

Here you will find field names and descriptions for our files.
User Notes

Notes about changes and updates to geographic products.
Combined Documentation

View the available technical documents from the Geography program.
Changes to Counties and County Equivalent Entities: 1970-Present

Substantial county changes include all county boundary changes affecting an estimated population of 200 or more people.
Geographic Boundary Change Notes

Geographic Change Notes are selected geographic changes to incorporated places, census designated places, county subdivisions, counties and equivalent areas.
Geographic Codes

Here you will find information about the various codes we use and crosswalks between codes and geographic entities.
Geography Program Errata Notes

Information about identified errors and corrections involving geography data.

Page Last Revised - December 20, 2021

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