One of the most common mistakes in data analysis is assuming that geographic boundaries remain the same over time. This can lead to misinterpretations of trends, especially when using Metropolitan Statistical Area (MSA) data or Census tract data.
Many analysts track MSA employment, population, or economic growth without checking whether the MSA's boundaries have changed. This can create a false sense of growth or decline if new counties were added (or removed) from the MSA definition.
Example 1: MSA Growth – Real or Just a Redefinition?
Example 2: The Changing Cincinnati MSA
The Cincinnati, OH-KY-IN Metropolitan Statistical Area (MSA) is a prime example of how geographic boundary changes can impact data interpretation.
Why This Matters for Cincinnati MSA Data
National vs. Local Data Can Show Different Trends
Misinterpretation Risks:
· Check whether MSA boundaries have changed when analyzing data over time.
· Use historical datasets that apply consistent MSA definitions (e.g., BLS-adjusted MSA data for comparisons).
· Be cautious when using Census tract data over time, since past data is not adjusted to reflect current boundaries.
· Compare national, state, and local trends together to get a fuller picture.
· Always read the data source documentation to understand any adjustments.
Pro Tip: The Census Bureau provides official MSA delineation files that list boundary changes over time. You can access them here: Census Bureau MSA Delineation Files
Before making conclusions about regional growth, always ask:
Is this trend real, or is it just a change in how the area is defined?
Stay tuned for more insights on making sense of data!
Senior Director,
Center for Economic
Analysis & Development
Home
About
Media
Events
Contact
Center for Economic Analysis & Development
100 Nunn Drive
Business Academic Center 396
Highland Heights, KY 41099
Phone: (859) 392-2414
Email: cead@nku.edu