A UNITED STATES DEPARTMENT OF COMMERCE PUBLICATION THE 1970 CENSUS AND YOU bruary 1973 (Rev.) US DEPARTMENT OF COMMERCE Social and Economic Statistics Administration BUREAU OF THE CENSUS A general introduction to Census data ^Subjects ^Areas ^Reports vTapes ^Microfilm U.S. DEPARTMENT OF COMMERCE FREDERICK B. DENT, Secretary SOCIAL AND ECONOMIC STATISTICS ADMINISTRATION JOSEPH R. "WRIGHT, JR., Acting Administrator BUREAU OF THE CENSUS JOSEPH R. WRIGHT, JR., Acting Director ROBERT L. HAGAN, Deputy Director ROBERT B. VOIGHT, Chief Data User Services Office This pamphlet was written by GARY M. YOUNG under the general supervision of MICHAEL G. GARLAND, Chief, Data Access and Use Laboratory. First printing, August 1971. Revised February 1972 and February 1973- i -0. THE 1970 CENSUS — AND YOU A General Introduction to Census Data Can Census Data Help Me? Probably. Census data are put to a wide variety of uses. Housing authorities study information about characteristics of housing in their cities as an aid in selecting neighborhoods which would benefit from improvement programs. County and regional officials are interested in population shifts, change in the average family size, concentrations of the very young or very old and other characteristics of their areas which affect requirements for public services. Businessmen also find a knowledge of such characteristics helpful in marketing their products. In the 1970 census, information was collected on such subjects as age, race, education, income, ownership or rental of houses and apartments, and number of rooms in houses and apartments. While you cannot obtain information from the Census Bureau about specific individuals or homes because this is forbidden by law, you can obtain summary information about geographic areas such as city blocks, groups of blocks, cities, counties, and States. By summary infor- mation we mean counts of persons or housing units with particular charac- teristics, such as the number of men 25 to 34 years old, families headed by females, housing units renting for $150 to $200 per month, or persons resid- ing in a certain city. Consider a few examples of the use of summary data: - A businessman interested in locating a new store will want to find an area with a high proportion of likely customers, such as families with moderate incomes, single young adults, or college graduates. - A school administrator may want figures for different parts of his city on the number of children under 5 years old for use in planning adequate future facilities, or the number of adults who have not completed high school in order to choose neighborhoods for adult education classes. - A neighborhood citizens' group, interested in improving services pro- vided by the city, may want data on the number of children in various age groups to support requests for recreational facilities or on the number of working mothers with children under 6 to indicate the need for child day-care centers. So, if you need to know the characteristics of the people and housing units within an area or want to know where people or housing units with particular characteristics are located, more than likely there are census data that can \ — o> \ — CD 1 .£ o p vD o> cj *~ •H T3 a ID o T3 co =3 ■H H U o cd .g S w o en J o a § CD CD -P En b£ •H aJ rH bo CD G > •H o CO o d o T3 A 9 TJ • -P c3 O d H CD G CD -P O X> fl •H O -p a o XI CD P H ft « |- H CO CO 6 CD XI P Eh -H v> t? o o o o o o o o o o o o o o o o o ■6?. moo i o o (MOO o o i o o in o i o o cm o o o O O O I CM CM CM CM CM m in us o in m (M CM CM CM CM CM m in m in m inmininmininininin O O O in O CM CM CM CM O m in m in iminm I cd o 3 -P -H 0) 0) -p 43 iH -H ■PEC •rt O O P.-H 3 O CO -p rH 43 id co -P 3 cd r-i 3; b. -P ■2 c SOD P E S-. 43 cd 3 p co 3 cd cd cu co -P 3 -P 3 -P 3 a) cd cd u -P v co cd -P > v >> cd o co « «) h C£ E 3 -P cd -P E iH 3 o 3 O cd O cd O lUCOU^UCOUCOU CQcriE-<0>0>S O -P 3 ho cu E cd cm P, *h O -h 3 3 -P to o* o $* e CD bO -P 3 3 ra O "H P.-P u e cd cd O CD CD O X >H U CO CD -p CD cd 43 Cm -P CD Cm ^ CO T3" CD 3 rH cd cd -p cd bo 10 « C ^ -H 3 o E ■H T3 CO > cd m CD (D o o bo m m cd 45 3 5 -P O cd cd w w en 3 43 O o o E M -P •H 3 0) Stj co« ( 43 O t CO CO CO O Cl 0) CD cd o a -p -p J3 CD CD -H O O O CO E rH TJ O rH rH 'H O CD cd CD OOOItHKCO u<* fee. o o o o o o o o o o o o o o o o o o o o ooooooooo CMCMCMCMCMCMCMCMCM m in in in in m in I m i i i H o 43 B CD CO r) 3 P o ^ 43 3 P. CD Cm E O c o CD M M cd CD 3 CO -P -P O CO U 3 CO W 'H 3 (0 ^■HT>-PcdCd43T3M f Orl llHrl 5 C cj C O -H - 3 43 43 o o o O CO ID X U bo cd cd h2 ■p X , C M CD O !* co ■H ti , a 3 6 O , w x : (3 m O •h >> -P +J (D CD E E O O o o cd cd cd ID rH E CD >. cd >>> E CO O O ■P MO CO T] P. K cd C E -H rH S CD I M CD CD -i CD O *-t CD CO O O CD O 3 cd 43 -p cd cd H O »H « a, w > a. s 3 C Cm cd cd O O N O O +^ •H 3 cd +> CD O. cd co 3 O CD O O M V > Ol, o n S 5,-1 o "i ? i ^.S e 'o B-o"? J: « S-m Jj w »j .93 §-8 S c - 2 s o o c c e e •-« E J3 e CV ^ e2 * *• B a - a^ _4j _CW etc 00 <7> w K.i-5= 1 H CM -c-,^t^ - A - Political units of the Nation , including States, congressional districts, counties, minor civil divisions (e.g., towns, precincts, and townships) ,* incorporated places (e.g., cities and villages), and wards in some cities. Both 100 percent and sample data summaries are prepared for these areas, except for wards (population counts only). Statistical areas, (listed in order according to diminishing average population size), such as: — standard metropolitan statistical areas (SMSA's — comprising a county containing a central city of 50,000 or more plus contiguous counties socially and economically integrated with the central county. Both 100 percent and sample data.) — urbanized areas (UA's — comprising a central city plus the surround- ing closely settled urban fringe. Both 100 percent and sample data.) — unincorporated places (a concentration of population which is not incorporated. Only unincorporated places of 1,000 or more inhab- itants are shown in the reports. Both 100 percent and sample data.) — census tracts (subdivisions of SMSA's, averaging 4,000 population, covering all SMSA's for 1970. Both 100 percent and sample data.) — enumeration districts (ED's — administrative divisions set up by the Bureau to take the census in areas where enumerators were used, averaging 800 population. Only 100 percent data.) — block groups (groups of city blocks, averaging 1,000 population, which are the equivalent of enumeration districts in 145 of the large metropolitan areas where the census was taken by mail in 1970. Only 100 percent data ) — blocks (city blocks, generally rectangular areas bounded by four streets, defined in cities of 50,000 and over plus their suburbs and in additional cities which contracted with the Bureau for block tabulations. Only 100 percent data.) How Are Census Data Released? Printed Reports Printed reports have long been the most common means of releasing census data. If you do not require information in great detail for a large number of areas, 'In 21 States minor civil divisions (MCD's) are not adequately defined for report- ing census statistics. To take their place, Census and local officials have designed census county divisions (CCD's) COMMON CENSUS GEOGRAPHIC AREAS Illustration 1 AREA STANDARD METROPOLITAN STATISTICAL AREA AND COMPONENT AREAS (central city of 50,000+ population and the surrounding metropolitan county(s)) Central City Urbanized Area (shaded area) Place Minor Civil Division County CENSUS TRACT (small, homogeneous, relatively permanent area; all SMSA's are entirely tracted) „.; -•* ,0, 10?» ,0, bia JOS rem : ■ o,-l ,0, c h m il » » "" %°* H3 III ,.. "°° Ml ;>' „„",,, Ml is 1 IS II, » 1 ISj ^ '«ILL l»»I IT S 8 ,0. u ; ' "; ?01- «XCN SOI 03 1 1 3.06 * H*» c_ W 3^*1 * 1 1 : « I ! i ilA |> 309 ; 3 i 1 i i"« ,'■1 1 POPULATION SIZE — At least 50,000 Average 4,000 BLOCK GROUP OR ENUMERATION DISTRICT (subdivisions of census tracts, places, and minor civil divisions) BLOCK (identified in all urbanized areas and some selected areas) 301 l- 302 PINE 305 ST. 306 H Q Z CM 307 PINE 303 h- 304 308 IU o Ul 317-1 _J O u 316 SPR 313" UCE 309 ST 312 315 314 311 310 Average 1,000 Average 100 - 6 - the printed reports will probably be the most convenient and readily available source for you. The data presented in 1970 census reports are similar in kind and quantity to the data contained in reports re- sulting from the 1960 census. Your local library may have the reports you need, or you may purchase copies, usually for less than $2, from the U.S. Superintendent of Documents. Order forms can be obtained from the Census Bureau (see page 11) or the nearest U.S. Department of Commerce field office. The census data contained in printed reports are arranged in tables. Population and housing characteristics for specified areas are reported, such as the number of rented housing units in a block, the number of families below specified income levels in a census tract, or the number of persons who have had vocational training in a city or county. Illustration 2 presents an example of a table such as you will find in printed reports. The Census Bureau releases several different series of reports, and in most series, there is one report for each State. Some contain data principally about people and families; others contain data primarily about housing. You will find selected report series briefly described in Table 2. All the reports in these series are in print. Summar y Tapes There is practically no limit to the number of combinations or cross- tabulations of census data which may be prepared for an area. For example, in reporting for a particular county, a count of males could be given, or a count of males by single years of age, or a count of males by single years of age by race, and so on. Releasing census summary data on computer tapes ("summary tapes") makes it possible to include more tabulations, greater detail, and more geographic areas than it is feasible to publish in printed reports. The summary tapes have the same kind of data as found in printed reports; there is just more of it. Many census data users will be able to find the information they need in the Bureau's printed reports. But if frequent and extensive use is planned, summary tapes may be the most reasonable approach because of the speed and relative convenience of machine processing. Also, since there are many cross-classifications on the tapes which are not pub- lished, some users may find the tapes essential to meet their data requirements. Census summary tapes may be purchased from the Bureau at $70 per reel if the user wants direct access to the data c Six series of summary tapes are available, involving about 2,000 reels of computer tape. (See table 3.) In considering this approach, it is important to keep in mind that there will be expenses for personnel time, programming, and computer operation. As an alternative, users may wish to obtain data services from other organizations which are purchasing the tapes. Over 170 organizations have advised the Bureau of their plans to obtain tapes and furnish data services. These "Summary Tape Processing Centers" will be discussed in greater detail later. -7 - TABLE 2 S elect Reports 1 970 Census of Population and Housing Series PC(1)-A Number of Inhabitants . Final official population counts are presented for States, counties, SMSA's, urbanized areas, (One per State) minor civil divisions, census county divisions, all incor- porated places, and unincorporated places of 1,000 inhab- itants or more. Series PC(1)-B General Population Characteristics . Statistics on age, sex, race, marital status, and relationship to head of (One per State) household are presented for States, counties, SMSA's, urbanized areas, minor civil divisions, census county divisions, and places of 1,000 inhabitants or more. Series PC(1)-C General Social and Economic Characteristics . These reports will focus on the population subjects collected on a sample (One per State) basis Each subject is shown for some or all of the following areas: States, counties, SMSA's, urbanized areas, and places of 2,500 inhabitants or more. Series HC(1)-A General Characteristics for States, Cities, and Counties . Statistics on 100-percent housing subjects are presented (One per State) f° r States, counties, SMSA's, urbanized areas, and places of 1 ,000 inhabitants or more Series HC(1)-B Detailed Characteristics for States, Cities, and Counties . These reports focus on the housing subject collected (One per State) on a sample basis. Each subject is shown for some or all of the following areas: States, counties, SMSA's, urbanized areas, and places of 2,500 inhabitants or more. Series HC(3) Volume III. Block Statistics . One report for each urbanized area showing data for individual blocks on selected 100-percent (One per UA) housing and population subjects. The series also includes reports for the communities outside urbanized areas which have contracted with the Census Bureau to provide block statistics from the 1970 census. Series PHC(1) Census Tract Reports . One report for each SMSA, showing data for most of the population and housing subjects included in (One per SMSA) the 1970 census. Some tables are based on the 100-percent data, others on the sample data ILLUSTRATION 2 Table 117 Social and Labor Force Characteristics for Places of 2,500 to 10,000: (PC(l)-C for the State of Maryland) Places PLACE OF BIRTH Total population Foreign born _ Native Born in Stote ot residence Born in different State Northeost North Central South _. West Born abroad, al seo. etc State ot birth not reported RESIDENCE IN 1 96S Total population, 5 years old and over Some house Different house in United Stotes Some county Different county Same State Different State Northeost North Central South _ West.. Abrood . Moved, 1965 residence not reported SCHOOL ENROLLMENT Percent enrolled, 3 to 34 years old 3 ond 4 yeors old _ , 5 ond 6 years old 7 to 13 years old 14 ond 15 yea's old 16 ond 17 years old 18 and 19 years old 20 ond 21 years old 22 to 24 yeors old 25 to 34 yeors old. YEARS OF SCHOOL COMPLETED Total persons, 25 years old and over No school yeors completed Elemeniory I to 4 years 5 to 7 yeors _ _. 8 yeors High school 1 to 3 years 4 yeors College 1 to 3 yeors 4 yeors or more.... . Median school yeors completed EMPLOYMENT STATUS Male, 16 years old and over Labor force . .. Percent ot total . . ............ . Civilion lobor force . Employed. Unemployed _. . __ _. Percent of civilian labor force Not in labor force Under 65 yeors _. 65 yeors ond over 1970 Cormody Hills-Pepper Chopel c 3lverton Capitol Mill Village Oaks-Cedar Chester- Colesville Columbia Corol Hills (U) Heights (U) Heights (U) town Cheverly (U) (U) (U) Crisfield 6 S3S 2 713 6 295 6 020 3 476 6 66S 9 438 8 701 7 252 3 075 346 62 15 9 36 307 408 250 143 _ 6 189 2 651 6 280 6 on 3 440 6 358 9 030 8 451 7 109 3 075 2 220 816 1 908 1 780 2 147 1 990 2 615 2 963 2 024 2 579 3 777 1 545 3 494 2 788 1 099 4 035 6 069 5 106 4 159 385 1 021 135 184 184 575 1 051 1 892 2 200 455 121 483 90 51 138 104 497 957 995 215 8 2 147 1 309 3 165 2 440 391 2 381 2 893 1 704 3 421 242 126 11 94 26 29 106 327 207 68 14 51 18 40 29 10 65 113 144 58 10 141 272 838 1 414 184 268 233 238 868 101 S 682 2 499 5 471 5 412 3 272 6 196 8 572 7 462 6 408 2 904 1 777 1 287 1 012 3 131 1 499 3 932 2 990 647 2 177 1 543 3 675 960 2 940 1 623 1 583 1 866 4 900 6 077 2 958 1 234 1 440 372 676 376 528 1 107 1 930 287 561 993 2 235 588 2 264 1 247 1 055 759 2 970 5 790 2 397 241 1 296 12 131 39 439 128 932 2 658 119 176 939 576 2 133 1 208 616 631 2 038 3 132 2 278 65 219 10 64 87 309 126 647 1 283 77 10 49 _ _ 64 86 47 205 721 57 _ 589 566 2 022 957 152 374 1 041 974 2 071 55 82 _ 47 100 69 84 145 154 73 - 108 94 129 14 7 113 280 271 11 13 122 158 1 390 644 183 285 402 467 1 262 114 61 5 61.5 51.9 48.2 61.0 60.5 73.0 53 7 50.1 60 4 35.0 - 175 135 _ 179 48 7 39 4 166 93.0 68.2 78 5 798 972 99 9 87 8 71 3 84 8 99 1 99.9 93.7 93 7 96 994 97 3 99 9 966 99.9 96.8 999 86.4 95.0 89.2 968 98.8 84.0 82.9 99 9 93 7 94.0 91 .8 96 4 99 9 93.8 99.9 87.5 78 5 48.9 90.1 686 71 9 79 60 5 63.0 29 7 66 69.7 44 7 87 7 38.8 26 7 - 172 3 1 10 33.9 13.5 28.7 19.5 111 12 1 26 5.3 54 48 89 10.3 89 8.2 - 3 274 1 357 2 658 3 106 1 746 3 618 4 685 4 269 3 637 1 884 10 16 18 38 8 - 58 - 37 35 10 67 54 166 92 39 31 _ 89 157 59 212 200 409 262 141 112 40 363 486 58 164 170 244 120 173 111 73 335 181 341 382 699 820 442 523 328 236 957 642 1 287 425 852 955 304 1 337 1 297 912 1 200 216 542 51 299 218 257 664 946 838 372 119 967 40 366 256 261 741 1 802 2 170 284 48 129 107 122 11 5 11 7 12 7 143 160 120 9 4 1 912 787 1 596 1 946 1 275 2 253 2 737 2 515 2 187 960 1 647 654 1 380 1 553 868 1 855 2 369 2 327 1 853 731 86 1 83 1 86.5 79 8 68 1 82 3 866 92 5 84.7 76 1 1 643 639 1 318 1 525 854 1 840 2 339 2 283 1 779 720 1 640 626 1 318 1 467 828 1 810 2 277 2 257 1 750 627 3 13 _ 58 26 30 62 26 29 93 02 20 _ 3.8 3.0 1 6 27 1 1 1 6 129 265 133 216 393 407 398 368 188 334 229 239 76 199 290 300 288 289 138 216 96 26 57 17 103 107 no 79 50 118 133 Microfiche and Microfilm Microfiche copy of the printed reports can be obtained from the National Technical Information Service, The microfiche (4" x 6" cards of micro- film containing 60 images of report pages) dramatically reduces the amount of storage space needed. Because of this, libraries and other organizations planning to hold large numbers of reports may prefer to obtain microfiche , rather than the bulkier printed materials. Request order forms from the Census Bureau. - 9 - TABLE 3 1970 Census Summary Tapes Summary Tape Series* Areas Reported Type of Data No. of Tables and Data Cells for Each Area** First Count State, Congressional District, County, MCD or CCD, Place, and Block Group or Enumeration District 100 percent 54- tables containing 4.00 cells Second Count State, SMSA and Component Areas, County, MCD or CCD, Place, and Tract 100 percent 93 tables containing 3,500 cells Third Count Block 100 percent 36 tables containing 250 cells Fourth Count State, SMSA and Component Areas, County, MCD or CCD, Place, and Tract 100 percent and sample 327 tables con- taining 13,700 cells (more for State, County, and SMSA and Components) Fifth Count ZIP areas (3-digit areas nationwide; 5- digit areas only in SMSA's) 100 percent and sample 53 tables containing 900 cells Sixth Count State, SMSA, Metro. County, City of 50,000+, Central City 100 percent and sample 44-0 tables containing 260,000 data cells *Ref erred to as "Counts" by the Census Bureau, e.g., First Count, Second Count, etc. **A table, for example, might show the count of persons who are white, Negro, and other races. In this case, the table would have three cells. - 10 - Microfilm of First Count summary tape data is available from the Bureau, and paper copy prepared from the microfilm can also be obtained. Technical documentation is needed to read the data because the standard descriptive information is not contained on the tables. Are the Data All That I'll N eed? No. First of all, you will need maps. It Is of no value to know that 103 people live in block #205 if you do not know where block #205 is. Printed report users will not have this problem, because the appropriate maps are included with each report. However, persons using summary tapes must either buy maps separately from the Bureau or obtain those printed reports which include the necessary maps. Summary tape users will also need computer programs to display data from the tapes and a listing of geographic areas with their code numbers to interpret the codes on the tapes. Each area from a block on up to a State is identified only by a numeric code on the tapes. H ow Can I Obtain Tape Data Without Buying the Tapes? If you need data found only on the tapes but don't wish to do the necessary processing yourself, you may be able to find a Summary Tape Processing Center which will furnish the data and related services you need at an acceptable price. Since early 1969 the Bureau of the Census has recognized over 170 private, governmental, and academic organizations, at their request, as Summary Tape Processing Centers. The Census Bureau recognizes those organizations and groups which file a statement with the Bureau specifying their planned activities and indicating their intention to service the needs of census data users outside their organization. The centers are not established, franchised, or supported by the Bureau of the Census, and data products are available to them on the same basis as to all other data users. Each processing center establishes its own cost structure for services and may serve any interested client as it chooses. The Bureau sets no requirements. How Do I Get Starte d? Fill in the following "Request for Information About the 1970 Census" and mail it to the Data Access and Use Laboratory. If you anticipate regular and de- tailed use of census data, you should also obtain the 1970 Census Users' Guide , and subscribe to Small-Area Data Notes and Data Access Descriptions. Order forms are attached. REQUEST FOR INFORMATION ABOUT THE '70 CENSUS Data Access and Use Laboratory Data User Services Office Bureau of the Census Washington, D.C. 20233 Please send me samples of the Census Bureau's monthly newsletter ( Small-Area Data Note s) and occasional pamphlets ( Data Access Descriptions ) , a list of Summary Tape Processing Centers, order forms, and more information on the 1970 census. Name Organization Address City, State, & ZIP From the Bureau of the Census, U.S. Department of Commerce Small-Area Data Notes and Data Access Descriptions Small-Area Data Notes Eight pages (and sometimes more) each month bring you news of activities, products, and services in the field of small-area census data. Information on new publications, the release of data in both printed reports and summary tapes, and plans for upcoming surveys and censuses are featured. A special section highlights the applications readers across the country have found for census data in their areas— publications, workshops, computer programs, and other uses. Articles by Bureau staff members- specialists in their fields-explain technical points of census activities, census methodology, and processing techniques. Data Access Descriptions In addition to 12 monthly issues of SAD Notes, subscribers will receive, as they are_ issued, copies of Data Access Descriptions. These reports (ranging from 10 to 30 pages) provide more detailed information on Census Bureau products and subjects than is generally furnished in other Bureau publications. Each of the four to six issues released during a year deals with a different topic of interest. Subjects include the economic censuses, census geography, the summary tape counts from the 1970 census, the availability of low-income data, and printed reports. Both these publications are available to you in one subscription package for $5.50 per year— informative, interesting, up-to-the-minute news coupled with in-depth discussion. (please detach along this dotted line) SUBSCRIPTION ORDER FORM Enter Subscription (s) Small-Area Data Notes and Data Access Descrip- tions at $5.50 MAIL ORDER FORM WITH PAYMENT TO Publications Distribution Section Social and Economic Statistics Administration Washington, D.C. 20233 MAKE CHECK OR MONEY ORDER PAYABLE TO SUPERINTENDENT OF DOCUMENTS TOTAL AMOUNT $ O Payment enclosed OR Charge to: (Mark one) Superintendent of £ £tr»»t Arlrirpo: , .. D Check Documents Deposit □ Money order Account Number □ GPO coupons m w City. State, and ZIP Code 1 ) U.S. DEPARTMENT OF COMMERCE . Bureau of the Census key resources on Census '70 ORDER FORM Please indicate number of copies □ □ PARTS land 2of thel 970 Census Users' Guide @ $6.75 for both PART 1 only of the 1970 Census Users' Guide @ $2.00 per copy C3.6/2:C33/2/970-2/PT.1 □ PART 2 only of the 1970 Census Users' Guide @ $4.75 per copy C3.6/2:C33/2/970-2/PT.2 MAIL ORDER FORM WITH PAYMENT TO Superintendent of Documents U.S. Government Printing Office Washington, D.C. 20402 or any U.S. Department of Commerce District Office Make check or money order payable to: Superintendent of Documents TOTAL AMOUNT * Name Address City State Zip code 1970 Census Users' Guide Part 1 and Part 2 The 1970 Census Users' Guide is a two-part publication designed to furnish most of the information data users will need for effective access and use of 1970 census data products. Part 1 of the Guide (standard, paper-bound publication) includes the text and three appendixes. The text covers such subjects as the collection and processing of 1970 data, data delivery media (computer tapes, microfilm, and printed materials), maps and information on how to obtain census materials. The appendixes are: 1970 Census Users' Dictionary - defines concepts associated with population and housing tabulations and geographic areas relevant to the collection and publication of data. Comparison of Printed Reports and Summary Tapes summarizes and compares the contents of the reports and tapes. Glossary - defines many terms used in connection with collecting, processing, and publishing census data, and lists many abbreviations relevant to the census. Part 2 of the Guide (prepunched for 3-ring binder) contains appendixes specifically related to the use of census summary tapes and the Address Coding Guide. Technical Conventions and Character Set - present information on the physical characteristics, format, and languages associated with tapes released by the Bureau. 1st-4th Count Technical Documentation - describes the arrangement of geographic codes and census data on the first four series of summary tapes. Address Coding Guide Technical Documentation- furnishes informa- tion on the format and content of ACG's. Many data users will find both Parts 1 and 2 of great value. Part 1, with its comprehensive coverage of the decennial census program, data products, and related services, is an important instructional and reference tool. Part 2, concerned exclusively with computer tape products, is designed particularly for those who plan to obtain tapes or who want complete information on the data content of the summary tapes. PENN STATE UNIVERSITY LIBRARIES ADDQQ7ZA3E332