and services are produced, then applied to projected industry employment, and the resulting employment was summed across industries to get total wage and salary employment by occupation. Using this method, rapid employment growth is projected for health care workers while employment of railroad transportation workers is expected to decline, reflecting the projected change in the health care and railroad transportation industries, respectively.

Employment in an occupation also may grow or decline as a result of many other factors. For example, rapid growth is expected among teacher aides and educational assistants as increasing attention to the quality of education leads schools to hire more support staff. Rapid growth is also expected among computer systems analysts as technology advances and organizations place more emphasis on network applications and maximizing the efficiency of their computer systems. On the other hand, automation, the expanding use of computers, and developments in computer software will result in limited

growth or declining employment among many clerical workers, machine operators, and assemblers. The projected-year matrix incorporates these expected changes.

Data on self-employed workers in each occupation come from the Current Population Survey. Self-employed workers were projected separately.

Replacement needs. In most occupations, replacement needs provide more job openings than growth. Replacement openings occur as people leave occupations. Some individuals transfer to other occupations as a step up the career ladder or to change careers; some stop working temporarily, perhaps to return to school or care for a family; other workers-retirees for example-leave the labor force permanently. A discussion of replacements and the methodology used to prepare estimates is presented in Occupational Projections and Training Data, 2000-01 Edition, BLS Bulletin 2521.

The 1998 Standard Occupational Classification (SOC), with 822 detailed occupations, reflects the current occupational structure in the United States and was designed to provide a universal occupational classification system. All Federal agencies that collect occupational data will adhere to the new SOC. Information on the 1998 SOC, including its occupational structure, is available online. Internet: http://stats.bls.gov/soc/soc_home.htm

The 1998 Occupational Information Network (O*NET), with over 1,100 occupations, replaces the Dictionary of Occupational Titles and will be used by public employment service offices to classify and place jobseekers. For most occupations where the SOC and O*NET do not match, the O*NET provides more detail; in some cases, the SOC provides more detail. The 1998 O*NET was developed by job analysts. Future information on job duties, knowledge and skills, education and training, and other occupational characteristics will come directly from workers and employers. Information on O*NET is available from O*NET Project, DOL Office of Policy Research/ETA/ O*NET, 200 Constitution Ave. NW, MS N5637, Washington, DC 20210. Telephone (202) 219-7161. Fax (202) 219-9186. Internet: http://www.doleta.gov/programs/onet.

Nearly all occupational statements in this 2000-01 edition of the Handbook list the O*NET codes that relate to or match the definitions

used in the Bureau's 1998 Occupational Employment Statistics (OES) survey the principal source of occupational employment data in the Handbook. All numbers listed also appear in the table below. The table is arranged by 1998 SOC code, followed by the associated 1998 O*NET code-also known as the occupational unit (OU) code—and title, and the page on which the corresponding Handbook statement begins.

Notes

In 1999, the occupational classification in the Bureau's OES survey began to reflect the 1998 SOC. As a result, occupational statements in the 2002-03 edition of the Handbook, which is expected to be published in early 2002, will list the O*NET codes that relate to or match the SOCbased definitions used in the 1999 OES survey.

Comparability with older classification systems is important for analyzing long-term trends in employment and other worker characteristics. To simplify historical comparisons, BLS economists have developed a crosswalk showing the relationship between occupations in the 1998 OES survey and the 1999 SOC-based OES survey. The crosswalk is available from the Bureau of Labor Statistics, Office of Employment and Unemployment Statistics, Division of Occupational and Administrative Statistics, Room 4840, 2 Massachusetts Ave. NE, Washington, DC 20212.