Coding geographic areas across census years: creating consistent definitions of metropolitan areas

Area of Science:

• Demography
• Geographic Information Science
• Social Statistics

Background:

• US Census Bureau utilized distinct metropolitan area definitions and taxonomies in 1970, 1980, and 1990.
• Inconsistent geographic definitions across these census years create challenges for longitudinal analysis.
• Standardized metropolitan area data is crucial for historical demographic research.

Purpose of the Study:

• To propose a geocoding matching scheme for U.S. metropolitan areas across three decennial censuses.
• To enhance temporal consistency in metropolitan area definitions for research purposes.
• To facilitate comparative analysis of U.S. metropolitan changes over time.

Main Methods:

• Development of a geographic matching strategy to link metropolitan areas between census years.
• Comparative analysis of Census Bureau metropolitan area definitions and taxonomies.
• Creation of a crosswalk to reconcile differing geographic boundaries.

Main Results:

• A proposed matching scheme that maximizes consistency for U.S. metropolitan areas.
• Identification of discrepancies in metropolitan area definitions across the 1970, 1980, and 1990 Censuses.
• A framework for harmonizing historical metropolitan geographic data.

Conclusions:

• The proposed matching scheme improves the comparability of U.S. metropolitan area data over time.
• Consistent geocoding is essential for accurate historical demographic and urban studies.
• This methodology aids researchers in utilizing historical census data more effectively.