PUMA Criteria and Guideline Changes from 2000 to 2010 - Geography

Summary of Changes to the PUMA Criteria and Guidelines
from 2000 to 2010

Criterion	Census 2000 Criteria	Final 2010 Census Criteria
Levels of PUMA geography	Two levels of PUMA geography corresponded to the two types of PUMS files available (1-percent super-PUMA and 5-percent standard PUMA)	One level of PUMA geography corresponds to the one type of decennial and ACS PUMS available
PUMA minimum population threshold	100,000 persons	Each PUMA must contain a minimum population of 100,000 persons at the time of delineation. To assure ongoing publication of ACS PUMS and estimates, PUMA population should remain above 100,000 throughout the decade.
PUMA-county part minimum threshold	Not a requirement	Each single PUMA-county part meets a minimum population threshold of 2,400 persons (i.e., the Census 2010 minimum population threshold for a census tract (1,200) x2)
PUMA geographic "building block" entities	Counties or equivalent entitites, census tracts, incorporated places with populations of 100,000 persons or greater, and county subdivisions (minor civil divisions) in the 6 New England states	Counties or equivalent entities and census tracts only
PUMA names (guideline)	Not a requirement	*NEW - Names will be applied to PUMA areas and regions for local identification as designated by participants. Note: The provision of names is optional, and not a criterion/requirement