Documentation Notes to Accompany the Release of July 1, 1999 Population Estimates for Metropolitan Areas. Source: U.S. Census Bureau Internet Release date: October 20, 2000 The Census Bureau released July 1, 1999 metropolitan area population estimates to the public in October 2000. These MA population estimates are based on the July 1, 1999 county population estimates released in March 1999 and the July 1, 1999 subcounty population estimates released in October, 1999. The estimates include revisions of estimates from previous years and the results of special censuses and test censuses conducted by the Census Bureau. Central City - OMB designates the city with the largest population in each MSA or CMSA as a central city. Additional cities qualify for this designation if specified requirements are met concerning population size, commuting patterns, and employment/residence ratio. There are a few instances where only part of a city is central to an MSA/CMSA, because part of that city extends beyond the MSA/CMSA boundary and therefore is outside the MSA/CMSA. The word "part" is added to the central city name in each of these cases. An asterisk is appended to the names of central cities that represent the "remainder" portion of a consolidated city. A consolidated city results from the merger of a county with its principal incorporated place. The term "remainder" following a city name indicates that it is a part of a consolidated city-county government and that the populations of other incorporated places in the county have been excluded from the population totals shown here. The consolidated city remainders are as follows: Columbus, GA; Indianapolis, IN; Jacksonville, FL; Milford, CT; Nashville-Davidson, TN; Athens-Clark County, GA; and Augusta-Richmond County, GA. The central cities of a New England County Metropolitan Area (NECMA) are those cities in the NECMA that qualify as central cities of an MSA or a CMSA. County - A county is a type of governmental unit that is the primary legal subdivision of every state except in Alaska, where it is referred to as a borough, and Louisiana, where it is referred to as a parish. Cities that are independent of counties, such as Baltimore city, MD, are treated as county equivalents for data presentation purposes. CMSA - See Metropolitan Areas. FIPS Code - Federal Information Processing Standards (FIPS) codes uniquely identify each area, including states, MAs, counties, and subcounty entities (minor civil divisions and cities). The codes are issued by the National Institute of Standards and Technology of the U.S. Department of Commerce. Minor Civil Divisions (MCDs) - A minor civil division is a type of governmental unit that is the primary legal subdivision of a county in 28 states and is created to govern or administer an area rather than a specific population. The several types of MCDs are identified by a variety of terms, such as town, township, and district, and include both functioning and nonfunctioning governmental units. The MCDs in this report include towns and one reservation (in Maine). Metropolitan Areas (MAs)- MAs are defined by United States Office of Management and Budget (OMB) as a standard for collection and presentation of federal statistics. The general concept of an MA is that of a core area containing a large population nucleus, together with adjacent communities having a high degree of economic and social integration with that core. MA definitions are based on application of 1990 standards (which appeared in the Federal Register on March 30, 1990) to 1990 decennial census data. These MA definitions were announced by OMB effective June 30, 1993. Subsequent announcements have updated the MA definitions to June 30, 1999, based on Census Bureau population estimates and special census data. MAs include metropolitan statistical areas (MSAs), consolidated metropolitan statistical areas (CMSAs), and primary metropolitan statistical areas (PMSAs). An area that qualifies as an MSA and has a population of one million or more may be recognized as a CMSA if separate component areas that demonstrate strong internal, social, and economic ties can be identified within the entire area and local opinion supports the component areas. Component areas, if recognized, are designated PMSAs. If no PMSAs are designated within the area, then the area remains an MSA. Counties are the components of MAs, except in the New England states, where the components of MAs are cities and towns. Further information on MAs is available on the Internet at: . New England County Metropolitan Areas (NECMAs)- NECMAs are defined as a county-based alternatives for the city- and town-based New England MSAs and CMSAs. The NECMA for an MSA or CMSA includes: (1) the county containing the first-named city in that MSA/CMSA title (this county may include the first-named cities of other MSAs/CMSAs as well), and (2) each additional county having at least half its population in the MSAs/CMSAs whose first-named cities are in the previously identified county. NECMAs are not identified for individual PMSAs. There are twelve NECMAs, including one for the Boston-Worcester-Lawrence, MA-NH-ME-CT CMSA and one for the Connecticut portion of the New York-Northern New Jersey-Long Island, NY-NJ-CT-PA CMSA. Incorporated Places - Incorporated places include boroughs (except in Alaska and New York), cities, towns (except in New England, New York, and Wisconsin), or villages. The incorporated places in this report include cities and one borough (in Connecticut). PMSA - See Metropolitan Areas. Population (Census) - The April 1, 1990 population estimates base is a count of the number of people residing in an area (resident population) as reported in the 1990 census of population, or as subsequently revised. Revisions to an area's 1990 census population count may occur as the result of (1) post-1990 census corrections of political boundaries, or geographic misallocations, or documented under-enumerations or over-enumerations, and (2) geographic boundary updates made after the 1990 census, resulting from annexations, de-annexations, new incorporations, and governmental mergers. The closing date to include these two forms of revisions in this set of estimates was January 1, 1998. Population (Estimate) - The estimated population is a computed number of people living in an area (resident population) as of July 1. The estimated population at the place level is calculated by using the change in the number of housing units (from April 1, 1990 to the estimate date) at the place level to distribute population change separately derived at the county level. County estimates are calculated using a demographic components of change model that incorporates information on natural change (births and deaths) and net migration (net domestic migration and net movement from abroad) in the area since the reference date. Additional information on the methodology used to produce these population estimates is available on our Internet site at: . Puerto Rico - The metropoltian areas for Puerto Rico are agglomerations of municipios. The documentation for the population estimates process for municipios is available on our Internet site at: .