1 to 7 but are restricted to housing units with nonwhite household heads. Tables 9 to 11 are omitted for States having fewer than 25,000 units with nonwhite household heads. The subjects contained in each table are specified in the index on pages x and x1 in Parts 2 to 8 of Volume I.

Tables 12 to 17 are for SMSA's and their constituent parts (including each city of 50,000 inhabitants or more) and for urbanized areas. Categories for the items in these tables are shown in the same detail as in the tables for the State. Tables 12 to 17 are omitted for States with no SMSA's, urbanized areas, or places of 50,000 inhabitants or more (Alaska, Idaho, Vermont and Wyoming).

Less detail is presented in tables 18 to 27, which are for places under 50,000 inhabitants, by size groups. The amount of information varies by size of place, with minimum data for places of 1,000 to 2,500 inhabitants. Places of 25,000 to 50,000 inhabitants are covered in tables 18 to 21; places of 10,000 to 25,000 in tables 22 to 24; places of 2,500 to 10,000 in tables 25 and 26; and places of 1,000 to 2,500 in table 27.

County data are presented in tables 28 to 35. Tables 28 to 30 are for counties outside SMSA's (counties inside SMSA's are covered in tables 12 to 17). In the New England States, however, tables 28 to 30 are for all counties. Tables 31 and 32 are for rural-nonfarm housing and tables 33 and 34 are for rural-farm housing in all counties. Table 35, which presents data on source of water and sewage disposal, provides county totals excluding units in places which had 50,000 inhabitants or more in 1950 or in an interim census prior to 1960.

Tables 36 to 39 present statistics for housing units with nonwhite household heads for SMSA's and urban places (places of 2,500 inhabitants or more) having a specified number of such units-table 36 for 100 to 400 units, table 37 for 400 to 2,000 units, and tables 38 and 39 for 2,000 or more units. The number of characteristics and the amount of detail vary according to the number of units with nonwhite household heads. Tables 40 to 42 present statistics for housing units with white household heads having Spanish surnames in Arizona, California, Colorado, New Mexico, and Texas, or for housing units with Puerto Rican heads in the remaining States. Table 40 is restricted to SMSA's and urban places having 400 to 2,000 such units and tables 41 and 42 to areas and places having 2,000 or more. Tables are omitted if there are no SMSA's or urban places with the specified number of such units.

Data for most of the characteristics are based on samples of housing units; where the samples are of different sizes, the figures may not add precisely to the same totals. For example, the total for "all units" by condition and plumbing facilities may differ from the total for "all units" by number of bathrooms (see section on "Sample design").

Detailed tables in United States Summary chapter.-The detailed tables in the United States Summary chapter also are arranged by type of area; maximum detail is provided in practically all the tables. Table 1 presents summary characteristics for the United States as a whole and for each region, division, and State. Table 2 contains the same summary characteristics as table 1 but presents them for each region and division by inside SMSA's (separately for in central cities and not in central cities) and outside SMSA's, and by urban, rural-nonfarm, and rural-farm residence. Tables 3 to 8 present data on detailed characteristics for the United States and for each region, division, and State. The same detailed characteristics are presented in tables 9 to 14 for the United States by inside SMSA's (separately for in central cities and not in central cities) and outside SMSA's, and by urban, rural-nonfarm, and rural-farm residence, and in tables 15 to 20 In for each SMSA and place of 100,000 inhabitants or more. terms of the subjects and categories covered, tables 1 to 20 corre

contained in each table are specified in the index on pages XII and XIII of the United States Summary chapter (Part 1 of Volume I). Table 21 presents data on elevator in structure for large urban places. Although all places of 50,000 inhabitants or more in 1960 are listed in the table, data on elevator in structure are restricted to those places which had 50,000 inhabitants or more in 1950 or in an interim census prior to 1960. The data in table 21 do not appear in the State chapters.

Tables 22 to 29, covering data for the United States, regions, divisions, and States, are restricted to units with nonwhite household heads. Tables 22 and 23 parallel tables 1 and 2, respectively; tables 24 to 26 and tables 27 to 29 parallel tables 3 to 8 and 9 to 14, respectively. In tables 22 and 23, separate data are shown for areas having 400 or more units with nonwhite household heads, and in tables 24 to 26 separate data are shown for areas having 25,000 or more such units. With respect to the subjects and categories covered, tables 22 to 29 correspond with tables 8 to 11 in the State chapters.

Table 30 is limited to SMSA's and places having 10,000 or more units with nonwhite household heads. The items covered in this table (household equipment and number of bathrooms) are not included in the tables for nonwhite occupied units in individual areas and places in the State chapters.

Data for States and for the large SMSA's and places in the United States Summary chapter (except as noted for table 30) are taken from the tables in the individual State chapters. The tables in the State chapters, however, cover additional information. In the State chapters, data for States are presented by area and residence classifications and data for SMSA's are presented for the constituent parts of the area; for large urban places, the State chapters contain additional data for units with nonwhite household heads.

As in the State chapters, data for most of the items are based on samples of housing units. Distributions based on samples of different sizes may not add precisely to the same totals (see section on "Sample design").

Text tables in United States Summary chapter.-In the Summary of Findings in the United States Summary chapter, data on selected characteristics are presented in text tables A to Y. In addition to the 1960 data, statistics available from the 1950 and earlier censuses are included for purposes of comparison. For many of the characteristics, statistics are presented by inside SMSA's (separately for in central cities and not in central cities) and outside SMSA's. A limited amount of data is presented for the United States by urban, rural-nonfarm, and rural-farm residence, and for regions, divisions, States, and large cities.

Tables A, B, and C present counts of housing units in the inventory by geographic and residence classifications. Table E presents figures on the components of change in the housing inventory between 1950 and 1959 based on results of the December 1959 Components of Inventory Change survey, which is part of the 1960 Census of Housing. Tables D and F present counts of housing units and population. Tables G to K and M to V contain statistics on the various characteristics of housing units-by inside and outside SMSA's in most of the tables. Table L presents the counts of vacant units by condition and status; table W contains data on selected characteristics of urban and rural units (separately for rural-farm units in 1960); table X is restricted to characteristics of units with nonwhite household heads; and table Y is limited to characteristics of available vacant units. It should be noted that all available vacant units (both urban and rural) are included in table Y, except in the data on value and rent. The subjects and the area classifications covered in each table are specified in the index on pages x and x1 of the United States Summary chapter (Part 1 of Volume I).

The term "United States" when used without qualification in

and the District of Columbia.

For purposes of comparability, statistics in some cases are for conterminous United States, that is, the United States exclusive of Alaska and Hawaii; generally, the two States were excluded if comparable statistics for 1950 and earlier were not available for either or both States (see also section on "Housing data for Alaska and Hawaii"). In tables F and H, data for the early census years include statistics for Arizona, New Mexico, and Oklahoma, although they did not become States until after 1890.

Except for a few characteristics of vacant units, the 1960 figures are based on samples of housing units; where the samples are of different sizes, the figures may not add precisely to the same totals. Figures for 1950 are based on the complete count except for a few items which are based on 20-percent samples. Figures for 1940 and earlier also are based on the complete count. (For size of sample for individual items, see table I.)

To compare with the 1960 characteristics, the "not reported" categories in the 1950 and earlier data were eliminated by distributing the "not reported" cases in the same proportion as those reporting. Thus, the figures in the text tables reflect this adjustment of the published data. For the sample items in 1950, a further adjustment was made in the published 1950 data by ratio estimating the sample figures to the totals based on the complete count; this procedure was applied separately to the distributions for conterminous United States, Alaska, and Hawaii. For table W, the adjustment was made for urban and rural units independently of the total; therefore, the two 1950 figures in a category may not add to the total for the category, shown in other tables. Similarly, in table R the 1950 figures for "dilapidated or lacking plumbing facilities" for the United States and each State were adjusted independently; the sum of the figures for the States, therefore, do not add precisely to the figure for the United States.

Disclosure of data.-To avoid disclosure of information for individual housing units, characteristics are not shown if the base is four or fewer units. The base, for this purpose, is "all" housing units or "occupied" housing units except for value and rent data, for which the base is the number of units of the type for which value and rent were tabulated. For example, a distribution of units by gross rent is not shown if the number of renteroccupied nonfarm units is four or fewer.

Medians, averages (including population per occupied unit), and percentages are not shown where the base is smaller than the required minimum (see section on "Sample design"). Furthermore, percentages are not shown if they are less than the 0.1 minimum.

Leaders () in a data column indicate that either there are no cases in the category or the data are suppressed, for the reasons described above. Leaders are also used where data are inapplicable or not available.

A plus (+) or a minus (—) sign after a median indicates that the median is above or below that number. For example, a median of "5,000-" for value of property indicates that the median fell in the interval "less than $5,000” and was not computed.

MAPS, CHARTS, GRAPHS

Included in the United States Summary part and the State parts of Volume I are maps of the United States showing the regions, geographic divisions, and States, and the location and names of the standard metropolitan statistical areas as defined for the 1960 Census. Included in each State chapter is a map of the State showing the outlines of counties (parishes for Louisiana and election districts for Alaska) and standard metropolitan statistical areas, if any, and the location of places of 10,000 inhabitants or more. A map of each urbanized

The United States Summary chapter of Volume I also contains a number of maps, charts, and graphs (figures 5 to 20), which pictorialize some of the statistical findings from the 1960 and earlier censuses. In the charts and graphs which show data for 1950 and earlier, statistics for Alaska and Hawaii were included when comparable data were available (see section on "Housing data for Alaska and Hawaii"). The omission of these two States from some of the statistics is considered to have a negligible effect on comparability for the United States as a whole. Figures 5 to 20 are discussed in the Summary of Findings in the United States Summary chapter.

COMPARABILITY WITH 1950 CENSUS OF HOUSING

More subjects were covered in the 1960 Census of Housing than in the 1950 Census of Housing. Items which were added for 1960 are: Year moved into unit, duration of vacancy, presence of basement, elevator in structure, number of bedrooms, number of bathrooms, source of water, method of sewage disposal, clothes washing machine, clothes dryer, home food freezer, telephone available, automobiles available, air conditioning, and water heating fuel. In addition, access to unit and kitchen or cooking equipment were enumerated in 1960 as part of the determination of a housing unit; and number of acres in the place and sales of farm products were enumerated for the purpose of determining farm residence. On the other hand, information was collected in 1950, but not in 1960, on electric lighting, refrigeration equipment, and kitchen sink. Mortgage status, which was included in 1950, is covered in the Residential Finance program in 1960.

The above comparisons relate to subjects covered in the April enumeration of the 1960 and 1950 Censuses of Housing. Subjects enumerated in the Components of Inventory Change and Residential Finance surveys, started in late 1959 and completed in 1960 as part of the 1960 Census of Housing, are discussed in Volumes IV and V, respectively. Subjects enumerated in the 1950 Residential Finance survey also are discussed in Volume V of the 1960 Housing reports.

Some items in 1960 have more detail and a few have slightly less detail than the comparable items in 1950. Additional information was collected in 1960 on condition of housing units, type of heating equipment, description of trailers, description of vacant units not on the market, and number of television and radio sets. Slightly less detail is available in 1960 than in 1950 for type of structure and toilet facilities.

In 1950, information for most of the items was collected on a complete-count basis. For a few items, information was collected from 20-percent samples of units (see section on "Sample design").

The foregoing discussion applies specifically to conterminous United States. For a discussion of 1950 data for Alaska and Hawaii, see the section on "Housing data for Alaska and Hawaii."

Data from the 1950 Census for areas of the type covered in Volume I of the 1960 Housing reports are published in 1950 Census of Housing, Volume I, General Characteristics. Selected 1950 data are included in Volume I of the 1960 Housing reports in the United States Summary chapter (see also section on "Description of tables").

Changes since 1950 were made in the definitions of some of the major concepts, particularly in the concepts of unit of enumeration and farm housing. They were made in order to improve the usefulness of the data although it was recognized that comparability with previous censuses would be affected.

Procedures for collecting and processing the data in 1960 also differed from 1950. In this respect, the 1960 Census contained several innovations. One of the innovations was the use of forms

complete-count items, and the Household Questionnaire used in the more populous areas for sample items. Information for items not completed by the respondents was obtained by enumerators in direct interview. Other innovations included the division of the census period into two stages in the more populous areas, the greater use of sampling, the use of formal field review procedures, and the extensive use of the electronic computer and related equipment to process the data and produce the final tables. These innovations were designed primarily to improve the quality of the statistics and to reduce the time required to collect and publish the data; at the same time, they have introduced an element of difference between the 1960 statistics and those of earlier

censuses.

Changes and innovations are discussed in the sections on "Definitions and explanations" and "Collection and processing of data," which appear later in this report.

HOUSING DATA FROM OTHER CENSUSES

Many of the subjects covered in the 1940 Census of Housing are included in the April 1960 Census of Housing. The subjects specified above as having been added since 1950 were also added since 1940. One item, television sets, was enumerated in 1960, but not in 1940. On the other hand, information was collected in 1940, but not in 1960, on exterior material, lighting equipment, refrigeration equipment, estimated rentals of owner-occupied homes, and value and rent of farm dwellings. Information on conversion, which was included in 1940, is covered in the December 1959 Components of Inventory Change program as part of the 1960 Census of Housing.

Although the 1940 Census of Housing was the first complete census of housing, data on a few housing characteristics were collected in earlier years in conjunction with the decennial censuses of population. Statistics on the number of occupied units and population per unit, which are essentially comparable with current data but identified by various terms, are presented in reports on earlier censuses since 1890, with limited data back to 1850. In these reports, statistics are shown in terms of "homes," "families," or "private families." In some censuses, the statistics include quarters of "quasi-families" (quarters identified in the 1960 Census as group quarters). In addition, counts of units by color of household head are available for each census year since 1890, except 1910 when such data were available only for the Southern States. The classification by tenure has been reported since 1890. Mortgage status of owned units was included in the Censuses of Population from 1890 to 1920, and detailed data (including value of mortgaged property) were reported in 1890 for owned units that were encumbered (mortgaged). Value and monthly rent of nonfarm units and the number of units with a radio were included for the first time in the 1930 reports. Statistics on the number of dwellings and persons per dwelling also are available from the Censuses of Population from 1890 to 1930, the concept of "dwelling" being roughly comparable with the current concept of "structure"; in some of the censuses, information on number of families per dwelling was included.

The discussion in the above two paragraphs applies specifically to conterminous United States. For a discussion of 1940 and earlier data for Alaska and Hawaii, see the section on "Housing data for Alaska and Hawaii."

Data from the 1940 Census for areas of the type covered in Volume I of the 1960 Housing reports are published in 1940 Census of Housing, Volume II, General Characteristics. Selected data for 1940 and earlier are included in Volume I of the 1960 Housing reports in the United States Summary chapter (see also section on "Description of tables").

In some instances, concepts and procedures were not identical from census to census as discussed under the item in the section on

part, however, are not great enough to invalidate comparisons of the data. Comparisons with earlier censuses are restricted to censuses of housing and population, although information for a few characteristics related to housing was collected in censuses covering other subjects.

HOUSING DATA FOR ALASKA AND HAWAII

In censuses prior to 1960, the subjects and procedures for Alaska and Hawaii as territories differed somewhat from the standard program for States. Some items which were included in the census for States were omitted from the censuses in Alaska and Hawaii, and vice versa; and some items were not tabulated in the same detail as for States. Statements regarding the 1950 and earlier censuses appearing elsewhere in Volume I, apply specifically to conterminous United States; for Alaska and Hawaii, these statements should be modified where differences occurred.

Alaska. From the 1950 Census, which was the first census of housing in Alaska, data on the following items are available: Tenure and race, vacancy status, persons, and persons per room; number of rooms, year structure built, number of units in structure, and exterior material; condition and plumbing; water supply, toilet facilities, and bathing facilities; heating equipment and heating fuel, electric lighting, kitchen sink, and radio; and value of owner-occupied nonfarm units and contract rent of renter-occupied nonfarm units.

The 1950 definitions were the same as those used for conterminous United States with the following exceptions: For number of units in structure, no distinction was made between detached and other 1-unit structures; for the category "piped running water inside structure," no distinction was made between "hot and cold" piped water and "only cold" piped water; for heating fuel, utility and bottled gas were included in the cate gory "other fuel." For the 1950 data in the Summary of Findings in the United States Summary chapter (Volume I of the 1960 Housing reports), the number of units in 1-unit structures in Alaska was apportioned between "detached" and "other" on the basis of the 1960 ratio of "1-unit detached" to "1-unit attached" structures. Similarly, the number of units with piped water inside structure was apportioned between "hot and cold" and "cold only" on the basis of the 1960 ratio for such units. The effect of these adjustments on the comparability of 1960 and 1950 data for the United States as a whole is considered negligible. The detailed data and description of concepts for 1950 may be found in 1950 Census of Housing, Volume I, General Characteristics, Part 7.

For 1940 and earlier, data on a few housing characteristics were collected in conjunction with the censuses of population. In the 1940 Census (taken in Alaska in October 1939), only occupied units were enumerated. Data on the following items are available: Number of rooms, tenure, value of owner-occupied units (including farm units), and contract rent of renter-occupied units (including farm units). The population per occupied unit can be computed from the data available. Statistics on the number of occupied units and population per unit, which are essentially comparable with current data, are available from the Censuses of Population from 1930 back to 1900; in these reports, statistics are shown in terms of "homes," "families," or "private families." Counts by tenure, including the number of owned units that were encumbered, are available from the Censuses of Population from 1920 back to 1900. Statistics on the number of dwellings and persons to a dwelling also are available from 1900 to 1930, the concept of "dwelling" being essentially comparable with the current concept of "structure." The concepts are essentially the same as those for conterminous United States. For 1940 and earlier, the data may be found in the reports of the

Statistics by urban-rural and farm-nonfarm residence are available for 1950. For earlier censuses, however, housing characteristics have not been tabulated by residence (except for urban and rural figures on tenure and color for 1940).

Hawaii. From the 1950 Census, data on the following items are available: Tenure and race, vacancy status, persons, and persons per room; number of rooms, year structure built, number of units in structure, and exterior material; condition and plumbing; water supply, toilet facilities, and bathing facilities; electric lighting and refrigeration equipment; and value of owner-occupied units, value of vacant units for sale, mortgage status of owneroccupied units, contract rent of renter-occupied units, and rent asked for vacant units for rent.

The 1950 definitions were the same as those used for conterminous United States with the following exceptions: For number of units in structure, no distinction was made between detached and other 1-unit structures; data on value for owner-occupied units were restricted to units whose occupants owned both the unit and the land; and farm units were included in the data on value and rent. For the 1950 data in the Summary of Findings in the United States Summary chapter (Volume I of the 1960 Housing reports), the number of units in 1-unit structures in Hawaii was apportioned between "detached" and "other" on the basis of the 1960 ratio of "1-unit detached" to "1-unit attached" structures. For the 1950 data on vacancy status, the number of vacant units for seasonal occupancy was estimated from the "not available" group on the basis of the proportion of the 1960 "not available" units which were for seasonal occupancy. The effect of these adjustments on the comparability of 1960 and 1950 data for the United States as a whole is considered negligible. The detailed data and description of concepts for 1950 may be found in 1950 Census of Housing, Volume I, General Characteristics, Part 7.

For the 1940 Census, which was the first Census of Housing in Hawaii, data are available on the following items: Tenure and race, persons, and persons per room; number of rooms, number of units in structure, and exterior material; condition (state of repair); water supply, toilet facilities, and bathing facilities; lighting equipment, refrigeration equipment, and radio; value and mortgage status of owner-occupied units, contract rent of renteroccupied units, and the estimated rental value of owner-occupied and vacant units. The concepts reflect a few minor differences from those used for conterminous United States. The detailed data and description of concepts for 1940 may be found in 1940 Census of Housing, General Characteristics, Hawaii.

Statistics on the number of occupied units and population per unit, which are essentially comparable with current data, are available from the Censuses of Population from 1930 back to 1900; in these reports, statistics are shown in terms of "homes," "families," or "private families." Counts of units by tenure are available from 1930 back to 1900, and counts of owned units that were encumbered are available from the Censuses of Population from 1920 back to 1900. Statistics on the number of dwellings and persons to a dwelling also are available from 1900 to 1930, the concept of "dwelling" being essentially comparable with the current concept of "structure." The concepts are essentially the same as those for conterminous United States. Data for 1930 and earlier may be found in the reports of the censuses of population for Hawaii.

Statistics by urban-rural residence (but not farm-nonfarm) are available for 1950. For earlier censuses, however, housing characteristics are not available by urban-rural or farm-nonfarm residence.

1960 PUBLICATION PROGRAM

Final housing reports.-Results of the 1960 Census of Housing are published in Volumes I to VII and in a joint housing and population series consisting of reports for census tracts. A series

remainder of the final reports. Volumes I to IV and the census tract reports are issued as series of individual reports, with Volumes I and II issued also as bound volumes. Volumes V to VII are issued only as bound volumes.

The source of Volumes I, II, III, VI, and VII and the housing data in the census tract reports is the April enumeration of the 1960 Census of Housing. The special reports for local housing authorities are based on results of the April enumeration and, for most areas, on data collected at a later date for nonsample households.

Data for Volumes IV and V are based largely on the enumeration of units in a sample of land area segments, started in late 1959 and completed in 1960. The 17 selected metropolitan areas referred to in the description of the volumes (see page v) consist of the New York-Northeastern New Jersey and the ChicagoNorthwestern Indiana Standard Consolidated Areas and the following standard metropolitan statistical areas: Atlanta, Boston, Dallas, Detroit, Los Angeles-Long Beach, Philadelphia, Seattle, Baltimore, Buffalo, Cleveland, Minneapolis-St. Paul, Pittsburgh, St. Louis, San Francisco-Oakland, and Washington, D.C.-Md.-Va. The first nine areas named (the two standard consolidated areas and seven standard metropolitan statistical areas) are the areas for which separate data are included in Part 2 of Volume IV. The titles and contents of the reports are described on page V. For the most part, they are comparable to the reports published from the 1950 Census of Housing. The 1960 Volumes I, II, and VI are similar to 1950 Volumes I, II, and III, respectively. Volume III of 1960 corresponds to the series of reports on block statistics which constituted 1950 Volume V. Volume IV of 1960 has no 1950 counterpart but corresponds to Volumes I and III of the 1956 National Housing Inventory. Volume V of 1960 corresponds to Volume IV of 1950 and, in part, to Volume II of the 1956 National Housing Inventory. In 1950, census tract reports were published as Volume III of the 1950 Census of Population. Special reports for local housing authorities were published for 219 areas in 1950 Census of Housing, Series HC-6, Special Tabulations for Local Housing Authorities. Data of the type presented in 1960 Volume VII have not been published in previous census reports.

As stated on page v, data for the United States, regions, divisions, States, SMSA's, and large urban places are published in several series of housing reports. In some reports, cross-tabulations of housing and household characteristics are provided. Data for small areas, except for city blocks and census tracts, are restricted largely to those published in Volume I.

Preliminary and advance reports.-Statistics for many of the subjects covered in the census were released in several series of preliminary and advance reports. The figures in the preliminary and advance reports are superseded by the data in the final reports.

Population reports.—Population data are available for approximately the same types of areas that are covered in Volume I of the 1960 Housing reports. The data are published in chapters A, B, C, and D which constitute 1960 Census of Population, Volume I, Characteristics of the Population. For the United States and regions, detailed cross-classifications are provided in 1960 Census of Population, Volume II, Subject Reports, (Series PC(2) reports). Some of the reports in Volume II include data for States and SMSA's also. A more complete description of the publication program of the 1960 Census of Population may be found in any of the population reports.

AVAILABILITY OF UNPUBLISHED DATA

During the processing of the data for publication of Volume I, more data were tabulated than it was possible to print in the final reports. Some of the unpublished data from the April 1960

limited amount of additional data for housing units with nonwhite household heads has been tabulated but not published. For the larger areas (including SMSA's, States, divisions, regions, and the United States), virtually all the data that have been tabulated are published.

URBAN-RURAL RESIDENCE

Photocopies of unpublished data can be provided at cost. Certain special tabulations can be prepared on a reimbursable basis. Requests for photocopies or for additional information should be addressed to Chief, Housing Division, Bureau of the Census, Washington 25, D.C.

In general, urban housing comprises all housing units in urbanized areas and in places of 2,500 inhabitants or more outside urbanized areas. More specifically, according to the definition used in the 1960 Census, urban housing comprises all housing in (a) places of 2,500 inhabitants or more incorporated as cities, boroughs, villages, and towns (except towns in New England, New York, and Wisconsin); (b) the densely settled urban fringe, whether incorporated or unincorporated, of urbanized areas (see section on "Urbanized areas"); (c) towns in New England and townships in New Jersey and Pennsylvania which contain no incorporated municipalities as subdivisions and have either 25,000 inhabitants or more or a population of 2,500 to 25,000 and a density of 1,500 persons or more per square mile; (d) counties in States other than the New England States, New Jersey, and Pennsylvania that have no incorporated municipalities within their boundaries and have a density of 1,500 persons or more per square mile; and (e) unincorporated places of 2,500 inhabitants or more (see section on "Places").

Housing not classified as urban constitutes rural housing. Rural housing comprises a variety of residences, such as isolated homes in the open country and homes in small villages and environs of cities outside urbanized areas.

The 1960 definition of urban is substantially the same as that used in 1950; the major difference between the two is the designation in 1960 of urban towns in New England and of urban townships in New Jersey and Pennsylvania. The effect on housing classification arising from this change was actually small because, in 1950, most of the housing in such places was classified as urban by virtue of its location in an urbanized area or in an unincorporated urban place. In censuses prior to 1950, urban housing comprised all housing in incorporated places of 2,500 inhabitants or more and areas (usually minor civil divisions) classified as urban under somewhat different special rules relating to population size and density. The net effect of the earlier definition on population counts has been measured and is published in 1960 Census of Population, Volume I, Characteristics of the Population. The most important component of the urban territory is the group of incorporated places having 2,500 inhabitants or more. A definition of urban territory restricted to such places, however, would exclude a number of equally large and densely settled places merely because they are not incorporated places. Under the definition used previous to 1950, an effort was made to avoid some of the more obvious omissions by the inclusion of selected places which were classified as urban under special rules. Even with these rules, however, many large and closely built-up places were excluded from the urban territory.

To improve its measure of urban housing the Bureau of the Census adopted, in 1950, the concept of the urbanized area and defined the larger unincorporated places as urban. All housing in urban-fringe areas and in unincorporated places of 2,500 or more was classified as urban in 1950 as well as in 1960. The urban towns, townships, and counties as defined for the 1960 Census are somewhat similar in concept to the minor civil divisions classified

COUNTIES

The primary divisions of the States are, in general, termed counties, but in Louisiana these divisions are known as parishes. Alaska is divided into 24 election districts, which are included in Volume I as the equivalents of counties. There are also a number of cities which are independent of any county organization and thus constitute primary divisions of their States, namely, Baltimore in Maryland, St. Louis in Missouri, and 32 cities in Virginia. The District of Columbia, which is not divided into counties, also is considered the equivalent of a county, as are the three parts of Yellowstone National Park in Idaho, Montana, and Wyoming. There were 3,072 counties and parishes in the United States in 1960 and 62 county equivalents, making a total of 3,134.

The number of counties declined by three between 1950 and 1960. Armstrong County, S. Dak., was annexed by Dewey County; Elizabeth City County, Va., was consolidated with Hampton city; and Warwick County, Va., was consolidated with Newport News city. The number of county equivalents in conterminous United States increased by five. Five cities in VirginiaCovington, Galax, Norton, South Boston, and Virginia Beachbecame independent of county organization during the decade. Alaska was redistricted after 1950, and its judicial divisions were replaced by 24 election districts. Changes in the number of counties were fairly frequent some decades ago but have become progressively rarer. These changes, as well as changes of county boundaries, are listed in the notes to tables 6 and 7 in chapter A of the State parts of 1960 Census of Population, Volume I, Characteristics of the Population.

PLACES

The term "place" as used in reports of the decennial censuses refers to a concentration of population, regardless of the existence of legally prescribed limits, powers, or functions. Most of the places are incorporated as cities, towns, villages, or boroughs, however. In addition, the larger unincorporated places outside the urbanized areas were delineated and they are presented in the same manner as incorporated places of equal size. Furthermore, unincorporated places within urbanized areas are identified if they have 10,000 inhabitants or more and if there was an expression of local interest in their recognition. Finally, the towns in New England and townships in New Jersey and Pennsylvania recognized as urban are also considered places (designated in the tables by "UT"). In the State chapters, data are presented for (a) incorporated places of 1,000 inhabitants or more, whether outside or inside urbanized areas, (b) unincorporated places of 1,000 inhabitants or more outside urbanized areas, (c) unincorporated places of 10,000 inhabitants or more inside urbanized areas, and (d) those towns, townships, and counties recognized as urban. Statistics for places of 100,000 inhabitants or more are provided in the United States Summary chapter.

Political units recognized as incorporated places in the reports of the decennial censuses are those which are incorporated as cities, boroughs, towns, and villages with the exception that towns are not recognized as incorporated places in the New England States, New York, and Wisconsin. The towns in these States are minor civil divisions similar to the townships found in other