Home health aides, statisticians, solar-panel installers and software developers are among the 15 fastest-growing occupations in the U.S. and reflect the needs of an aging population, a shift to clean energy and employer demand for science, technology and math talent.

The number of solar photovoltaic installers -- responsible for installing systems on roofs or other structures, and earning a median annual wage of $39,240 in 2016 -- is projected to more than double from 2016 to 2026, according to data from the Labor Department’s biennial employment projections released Tuesday.

Eight of the remaining 14 fastest-growing occupations are in health care, with median salaries in 2016 ranging from $21,920 for personal care aides to $101,480 for physician assistants. The highest paid among them -- mathematicians -- earned a median $105,810 last year, but the position typically requires at least a Master’s degree.

As for the most rapidly declining jobs: typists, watch repairers, and postal workers are facing a bleaker outlook, the Labor Department data show.

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