Where the Jobs Are

America's aging population is changing the face of the country's work force, and the demographic shift is creating opportunities for mid-career job hunters and career changers.

Between 2010 and 2020, people 55 and older are projected to be the fastest-growing segment of the U.S. labor force, according to the 2012-13 Occupational Outlook Handbook, a jobs forecast released March 29 by the Bureau of Labor Statistics. In addition, healthcare professions are among of the nation's fastest-growing occupations.

The labor bureau's biennial report outlines trends in the U.S. population and economy, and forecasts the impact they'll have on a wide range of industries and jobs.

Here's a snapshot of workplace trends that are especially significant for people 40 and older:

1. The contingent of older workers is growing faster than any other demographic.

The number of Americans in the labor force 65 or older is projected to grow 11 times faster than the growth rate for the total labor force. The number of U.S. workers 55 to 64 years old will grow four times faster than the overall labor force growth rate, according to the report. The findings support other studies indicating people in their 40s, 50s and older want to work longer, out of necessity or desire.

2. Retirees and career changers are creating job opportunities for other workers.

Through 2020, most job openings will be created to replace workers who leave [pdf] to retire, change jobs, or go back to school. This replacement factor is expected to lead to especially high job growth in occupations such as office and administrative support, sales and health care, as well as education, training and library services.

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3. It pays to have a master's degree.

Jobs that require some type of master's degree are expected to grow the fastest through the end of the decade, by about 22 percent. Jobs that require a doctorate are expected to grow by 20 percent, followed by jobs that require an associate's degree (18 percent) or bachelor's degree (17 percent).

The slowest-growing occupations are those that don't require a college education. In sheer numbers, however, those positions are expected to account for the majority (63 percent) of new jobs.

4. Health services and personal-care jobs account for nine of the 20 fastest-growing positions.

Personal care and home-healthcare aides are projected to be the fastest-growing occupations through this decade. Those positions are relatively low paid -- with median annual salaries of around $20,000 -- and entry-level jobs don't require a high-school diploma.

However, a number of other fast-growth healthcare occupations have higher salaries, with a median annual wage of more than $45,000. Those include: biomedical engineers ($81,540), physical therapists ($77,400), diagnostic medical sonographers ($64,380), occupational therapy assistants ($51,010) and physical therapy assistants ($49,690).

Fast-growing occupations that aren't health related include market research analysts and marketing specialists ($60,570), brick masons and block masons ($46,930), marriage and family therapists ($45,720) and meeting and event planners ($45,260).

5. Registered nurses top occupations with largest number of new jobs.

Hospitals and other healthcare institutions will add 711,900 new jobs for RNs between 2010 and 2020 -- an increase of 26 percent from the previous decade, according to the report. Based on 2010 data, the median annual salary for an RN is $64,690.

Other occupations with the largest total number of new positions that pay a median annual wage of more than $45,000 include: high-school teachers, up 17 percent ($62,050); elementary school teachers, also up 17 percent ($51,660); and sales representatives in wholesale and manufacturing industries, up 16 percent ($52,440).

6. Farmers and childcare workers lead the ranks of the self-employed.

Despite the rise in freelancers and other sole proprietors brought on by the recession and other work force trends, the Bureau of Labor Statistics predicts overall slow growth for self-employed workers through 2020 [pdf]. Farmers, ranchers and other agricultural managers are projected to account for the highest percentage of self-employed workers, approximately 78 percent of a total of 1.1 million people with those jobs.

Other occupations with large numbers of self-employed workers include: construction managers (59.2 percent); real estate agents (52.5 percent); hairdressers, stylists and cosmetologists (42.3 percent); carpenters (35.2 percent); and childcare workers (31.7 percent).

7. Manufacturing and postal jobs head the list of dying occupations.

Although U.S. manufacturing output is predicted to increase through 2020, factory employment is expected to drop 1 percent during that time as jobs are phased out due to technology advances, changing business practices and other factors, according to the bureau. Jobs for shoe machine operators and tenders will drop by 53 percent, followed by decreases in positions for postal service sorters and processors (49 percent), postal clerks (48 percent), fabric and apparel patternmakers (36 percent), postmasters and mail superintendents (28 percent) and sewing machine operators (26 percent).

8. By 2020, a smaller percent of the U.S. population will be working.

Over the next eight years, the number of people 16 and older (excluding those in the military or in prison) with jobs or looking for work is projected to increase 6.8 percent, to 164.4 million. That's down from a 7.9 percent increase, to 153.9 million, between 2000 and 2010. Several factors are contributing to the trend, including slower population growth and the aging population.

Researching occupations: In addition to outlining population, economic and work force trends, the 2012-13 Occupational Outlook Handbook provides details on 536 occupations, covering close to 85 percent of all U.S. jobs. A summary for each occupation includes facts such as median pay and required education or training, as well as the employment outlook through 2020. The report, which is only available online, has a database that job hunters can search by median pay, education level, growth rate and total number of projected new jobs. It also includes a glossary of career terms and list of resources for learning more about specific industries or jobs.

Read more: 10 Hot Jobs for Career Changers