Occupational statements in the Handbook use key phrases to describe projected change in employment. The adjectives are based on numerical projections developed using the Bureau’s employment projections model system. Projections of occupational employment comprise the sixth and final step in the system; the six steps are listed in the discussion of methods below. A full description, including numerical projections of employment, appears in the November 1999 Monthly Labor Review, BLS Handbook of Methods, and in Employment Outlook: 1998-2008, BLS Bulletin 2522. The Winter 1999-2000 Occupational Outlook Quarterly presents the projections in a series of charts.

The projections reflect the knowledge and judgment of staff in the Bureau’s Office of Employment Projections and of knowledgeable people from other offices in the Bureau, other government agencies, colleges and universities, industries, unions, professional societies, and trade associations, who furnished data and information, prepared reports, or reviewed the projections. The Bureau takes full responsibility, however, for the projections.

Assumptions. The information in the Handbook is based on an economic projection, which is characterized by a labor force growing at the same rate as during the past 10-year period (1988-98), faster productivity growth, a constant unemployment rate, increasing trade deficits, and a Federal budget surplus. Other assumptions include moderate growth in Federal spending programs and above average growth in consumer spending on durable goods. Spending on food and beverages will grow more slowly than the average for all consumer expenditures, while spending on health care and other services, such as entertainment, recreation, and financial services, will grow faster. Investment in production equipment—including factory automation, communication, and computer items—will grow rapidly. Residential construction will grow with the population while nonresidential construction will make a comeback from depressed levels over the previous 10-year period.

Although the Bureau considers these assumptions reasonable, the economy may follow a different course, resulting in a different pattern of occupational growth. Real growth could also be different because most occupations are sensitive to a much wider variety of factors than those considered in the various models. Unforeseen changes in consumer, business, or government spending patterns and in the way goods and services are produced could greatly alter the growth of individual occupations.

Methods. This section summarizes the steps by which the Bureau arrives at projections of employment by occupation. BLS uses Bureau of the Census projections of the population by age, gender, and race, combined with projections of labor force participation rates—the percent of the specified group of the population working or seeking work—to arrive at estimates of the civilian labor force for the projected year.

BLS projections are developed in a series of six steps, each of which is based on separate projection procedures and models and various related assumptions. These six steps, or system components, deal with:

• The size and demographic composition of the labor force
• The growth of the aggregate economy
• Final demand or gross domestic product (GDP)
• Interindustry relationships (input—output)
• Industry output and employment
• Occupational employment

These components provide the overall analytical framework needed to develop detailed employment projections. Each component is developed in order, with the results of each used as input for successive components and with some results feeding back to earlier steps. Each step is repeated a number of times to ensure internal consistency as assumptions and results are reviewed and revised.

The projections of the labor force and assumptions about other demographic variables, fiscal policy, foreign economic activity, and energy prices and availability form the input to the macroeconomic model. This model projects GDP (sales to all final consuming sectors in the economy) and the distribution of GDP by its major demand components (consumer expenditures, investment, government purchases, and net exports). Estimating the intermediate flows of goods and services—for example, the steel incorporated into automobiles—is the next step in the projections process. The resulting estimates of demand for goods and services are used to project industry output of final products as well as total output by industry.

Industry output of goods and services is then converted to industry employment. Studies of trends in productivity and technology are used to estimate future output per worker hour, and regression analysis is used to estimate worker hours. These estimates, along with output projections, are used to develop the final industry employment projections.

An industry-occupation matrix is used to project employment for wage and salary workers. The matrix shows occupational staffing patterns—each occupation as a percent of the work force in every industry. The matrix covering the 1998-2008 period includes 262 detailed industries and 521 detailed occupations. Data for current staffing patterns in the matrix come from the Bureau’s Occupational Employment Statistics surveys, which collect data from employers on a 3-year cycle.

The occupational staffing patterns for each industry were projected based on anticipated changes in the way goods 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.