Only recent and limited data are provided by ZIP Codes. Statistics for smaller areas are sometimes withheld to avoid disclosing information about individual firms. Statistics from the basic economic censuses for Puerto Rico, the Virgin Islands, Guam, and the Northern Mariana Islands are published as the Census of Outlying Areas. These censuses have been taken in Puerto Rico since 1909, the Virgin Islands and Guam since 1958, and the Northern Mariana Islands since 1982. Most censuses are updated by publications with data which are collected by surveys with samples which are reselected every five years.
Reports based on sample surveys generally include measurements of sampling variability.
Many monthly and quarterly survey results are adjusted for seasonality. To the extent possible, concepts, definitions, and reporting units are consistent among the censuses, surveys and related programs. Census results supply the sample frames, benchmark statistics, and list of establishments and firms for surveys taken more frequently. Survey results can be reconciled with those from a census and vice-versa. When you move from census data to survey data, detail is lost.