Occupation and Industry
OCCUPATION AND INDUSTRY
Occupation and industry are key variables needed to describe and analyze the world of work experienced by men, women, and sometimes children in nations around the world and the changes that occur in this experience over time. These variables are also indispensable in describing the structure of national economies and their temporal dynamics. Briefly, occupation describes the type of work a person does and industry describes the main activity of the establishment in which the work is done (e.g., rice farmer in agriculture). Statistics on occupation and industry are usually collected by the official statistical organizations of individual countries through censuses or surveys designed to meet national needs for monitoring the economy and shaping economic policies. The range of activities defined as work affects the scope of statistics that will be collected by these organizations. Coverage of such statistics is typically limited to persons who were employed during some reference period, such as the week preceding the census or survey, although usual occupation is sometimes reported for the unemployed. Occupations of persons who are employed intermittently (such as poll workers on election days), are temporarily out of the labor force, or are producing goods and services for their own consumption only usually will not be included. These persons are often disproportionately women.
National statistical organizations in many countries have collected industry and occupation data in censuses and surveys for many years. In the United States decennial census, for example, questions on industry date back to 1820 and regarding occupation to 1850.
Industry and Occupation Classification
Once the agencies have collected information about the industry in which respondents work and the occupations they report, they must classify these responses into industry and occupational categories. While the industry and occupation classifications adopted are necessarily country-specific, there has been considerable progress over the last 50 years toward also ensuring international comparability of such statistics.
An industry category is designed to describe the activity of the establishment in which employed or self-employed persons worked during a specified reference period. It describes what the establishment does rather than what the individual does while employed there. Industry statistics have been collected in censuses and employment surveys in many countries, usually in response to questions regarding where a person works (including name and address of the establishment), or what the main products or functions of the establishment are. In order to facilitate comparisons of different data sources and data from different countries, it is desirable to have an internationally comparable industry classification. This type of classification scheme has been in existence since 1948 and is periodically revised. The United Nations Statistics Division recommends that countries code and tabulate industry data "… according to the most recent revision of the International Standard Industrial Classification (ISIC) of All Economic Activities" (United Nations, Principles and Recommendations for Population and Housing Censuses, Revision 1.1998, p. 86). Many other classification schemes exist, however.
The North American Industry Classification System (NAICS) was adopted by the United States, Canada, and Mexico, and used in their 2000 round of censuses. The overall structure of the classification is the same in all three countries, though the details differ. The United States version of NAICS, used to code Census 2000 industry responses, is a complete revision of the 1990 census classification and differs from the ISIC. The 1990 census published data under 13 major industry groups and 243 detailed industries; for Census 2000 there are 15 major groups and 265 detailed industry categories.
In any complex economy, people work in a wide variety of occupations. A classification scheme for occupations, similar to that devised for industries, must be adopted. The many existing schemes used by different governments all seek to organize the actual jobs people do into clearly defined groups, according to the tasks performed and/or the skills required. They provide guidelines as to how the jobs people report are to be classified into detailed occupational groups and how these detailed groups are to be aggregated into broader groups. Many national classifications are designed to be similar to or comparable with the International Standard Classification of Occupations (ISCO).
The version of ISCO employed in the early twenty-first century, ISCO-88, was developed by the Fourteenth International Conference of Labor Statisticians in 1987 and adopted by the International Labor Organization (ILO) in 1988. It consists of four levels of aggregation: 10 major groups; 28 sub-major groups; 116 minor groups, and 390 detailed occupational unit groups. The ILO, as custodian of ISCO-88, provides advice and assistance to countries in developing common classifications based on that classification system. The UN Statistics Division recommends that countries prepare tabulations of census data in accordance with ISCO-88 to facilitate international comparisons and communication among users of the data.
Full international comparability has not yet been achieved. An ILO review of 1990 census-round practices in 115 countries found that 65 countries could link their occupational data to ISCO-88, and another 33 to an earlier version of that system; others used national classification systems which were not comparable. In the 2000 round of censuses, many countries still used occupational classifications that were not directly comparable with ISCO-88.
In the United States until the 1970s, government agencies, notably the Department of Labor (and its Bureau of Labor Statistics) and the Census Bureau, used different and noncomparable occupational classifications. The 1980 U.S. Standard Occupational Classification (SOC) was developed concurrently with the 1980 Census Occupational Classification with the expectation that it would be phased in and used by all agencies. A secondary consideration in its development was comparability with ISCO-68. A major revision of the SOC was undertaken prior to the 2000 census, with many occupational categories added, deleted, or changed. There are now over 800 detailed categories. In the final Census 2000 Occupational Index these were aggregated into 509 detailed occupations, which are not directly comparable with those in the 1990 census or with ISCO-88.
History of Industry and Occupation Statistics
Statistics on industry and occupation are needed to monitor social and economic trends and to inform related policies. In the United States the census was mandated primarily to establish the basis for apportioning the House of Representatives. Yet, as early as the first census in 1790, the debates about its content reflected a view that governments at all levels need more detailed knowledge about the social and economic characteristics of the population. Several proposals on industry/occupation categories were made, including some by the future presidents James Madison and Thomas Jefferson. Eventually, a three-way classification was adopted, and applied in the census of 1820: agriculture, commerce, and manufactures. Today these would be viewed as industrial classifications. No occupational information was collected in 1830 but the question was included again in 1840. By this time the number of categories had been extended to seven: mining; agriculture; commerce; manufactures and traders; ocean navigation; navigation of canals, lakes, and rivers; and learned professions and engineers. While these categories gave a fuller depiction of the work people were doing than did the previous three, the categories still combined industry and occupation and omitted servants, government officials, clerks, and others.
The increasing division of labor in American society can be observed by noting the occupational classifications of each progressive census. The census of 1850 shifted from family to individual enumeration and separate schedules were provided for free persons and slaves. Information on occupation was acquired only for free males over 15 years old but greater occupational detail was collected. In 1850, 323 specific occupational categories were created under ten headings. In 1860 women as well as men over 15 years old were asked their occupations and the increasing complexity of the economy was reflected in the list of 584 possible choices. Between 1870 and 1930, persons ten years old and over were included in the occupational inquiry, reflecting the prevalence of child labor in the United States. In 1940 and later the age limit was 14 years old and over, reflecting the effect of child labor laws enacted in the early part of the century that prohibited or limited the paid work of children. Separate questions on occupation and industry were introduced in 1910, and the number of occupational categories
changed each decade: 303 in 1900, 469 in 1950, 509 in 2000.
Trends in Occupation and Industry Composition
These changes in coverage and in occupational categories reflected an expanding economy, greater division of labor, emergence of new jobs, and shifts in broad occupational areas, as well as major changes in the status of women and African Americans. In 1790, the nation was predominantly agricultural. By the mid-twentieth century, it had become predominately industrial and commercial. At the end of the twentieth century it was largely a service economy.
The census occupational data reveal a number of other striking changes over the course of the twentieth century. In addition to the movement from farm to non-farm work, the composition of non-farm work changed: The number of laborers declined, operatives and craftsmen increased, as did those in the service trades. The most significant twentieth century increase was observed in "white-collar" occupations, which went from about 18 percent of workers in 1900 to over 40 percent by 1980. According to the U.S. Department of Commerce in 2001, figures indicated that by 2000, white collar workers represented about 59 percent of the total employed.
Occupational trends were usually described in detail only for men until the last several decades when the increasing participation of women in the labor force required attention to their roles also. Trends in the distribution of occupations for women differed somewhat from men. There was a notable drop in private household workers throughout the twentieth century and significant declines in the operatives category as well. In contrast, trends for women were similar to those for men with respect to the number of farm workers and other types of manual work. Some convergence in occupational distributions was evident by 1980 although many more women were still in clerical and service work whereas men predominated in managerial and craft occupations. The convergence continued through 2000, though a substantial degree of occupational clustering by sex remains a characteristic of the labor force.
Industry Composition in 2000
In 2000 the total U.S. population was 281 million. Of this, the civilian non-institutional population aged 16 years and older was 209.7 million: 100.7 million males and 109 million females. The total number of employed persons was 135.2 million, or 64.5 percent of the total, of which 72.3 million were males and 62.9 million were females. A concise description of the industrial composition of the 135.2 million figure just cited is presented in Table 1. For each category, the proportion of females is also shown.
As Table 1 shows, by the beginning of the twenty-first century, the proportion of people employed in agriculture was only 2.4 percent of total employment–considerably less, for example, than persons employed in hospitals, 3.7 percent. Women had a share of employment that ranged from less than 10 percent in construction to 81.9 percent in social services–an industry in which total employment was also larger than the total employment in agriculture.
The radical transformation of the industrial-occupational structure away from agriculture, first toward manufacturing and then from manufacturing toward service industries, is also reflected in the statistics of other high-income countries, although to a lesser degree than in the United States. Table 2 presents the broad distribution of the civilian labor force by major industrial sectors in selected high-income countries.
Bradley, Dana and Katharine Earle. 2001. "Developing and Explaining the Crosswalk between Census 1990 and 2000 Industry and Occupation Codes." Proceedings of the Annual Meeting of the American Statistical Association August 5–9,2001. American Statistical Association.
International Labour Office. 1990. International Standard Classification of Occupations: ISCO—88. Geneva, Switzerland: International Labour Office.
International Labour Office. 1996. "Sources and Methods: Labour Statistics." Total and Economically Active Population, Employment and Unemployment, 2nd edition. Geneva, Switzerland: International Labour Office.
International Labour Office. 2001. "Asking Questions on Economic Characteristics in a Population Census." STAT Working Papers, No. 2001–1 pp. 4–48. Prepared by R. Gilbert. Geneva, Switzerland: International Labour Office, Bureau of Statistics.
Nam, Charles B. and Mary G. Powers. 1983. The Socioeconomic Approach to Status Measurement. Houston, TX: Cap and Gown Press.
United Nations. 1998. Principles and Recommendations for Population and Housing Censuses, revision l. Statistical Papers. Series M No. 67. New York: United Nations.
U. S. Census Bureau. 2001. Statistical Abstract of the United States: 2001 Washington, D.C.: U.S. Government Printing Office.
Mary G. Powers