Puerto Rico and the island areas were enumerated as part of the Census2000 operation, with a census day of April 1, 2000. Puerto Rico processing will be done with the rest of the U.S. while the island areas will be processed separately because the questionnaire was modified to fit local needs.
For the 1990 census, the Census Bureau undertook the enumeration cooperatively with the governments of the following six entities:
The Commonwealth of Puerto Rico
The Virgin Islands
American Samoa
Guam
The Commonwealth of the Northern Mariana Islands
The Republic of Palau (which has since become independent)
Because characteristics of the outlying areas differ, the presentation of census data for them is not uniform. The 1960 Census of Population covered all of the places listed above except the Northern Mariana Islands (their census was conducted in April 1958 by the Office of the High Commissioner), while the 1960 Census of Housing also excluded American Samoa. The 1970, 1980, and 1990 Censuses of Population and Housing covered all areas.
