For directions on reading the variable description see Data Dictionary Introduction.

Availability: 
 

1850	1860	1870	1880	1900	1910	1920	1940	1950	1960	1970	1980	1990
										M

Universe: 
Households and group quarters in the Metro samples. 

Description/Comparability: 
CNTYGP97 is an unrecoded variable that identifies the household's 1970 county group of enumeration. 

Users must consult the 1970 PUMS maps in order to interpret the codes, see "Geographic Tools" in Volume 2: User’s Guide Supplement. The first three digits correspond to county-group areas designated by the United States Bureau of Economic Analysis, Regional Economics Division. These areas consist of an urban center and surrounding counties where economic activity is focused directly or indirectly on that center. Usually, they are metropolitan areas extended to include all counties for which that metropolitan area’s central city is the trade and labor market center. They can and frequently do cross state lines. In areas not near any metropolitan area, the county-group areas are usually centered on the largest city in the area. Many county groups are divided into two or more subareas, which often identify metropolitan areas or county components of metropolitan areas with 250,000+ residents; they sometimes combine two smaller, adjacent metropolitan areas to make a subarea with 250,000+ residents; some of them are merely residual areas. For confidentiality reasons, there are no county-group areas or subareas with fewer than 250,000 residents. 

Though they have different boundaries, 1970 county groups are similar in conception to 1980 county groups (available in CNTYGP98) and 1990 Public Use Microdata Areas (available in PUMA). For further explanation of metropolitan areas see METAREA. 

Codes: 
See "Geographic Tools" in Volume 2: User’s Guide Supplement for the original 1970 sample maps and county group composition.