WASHINGTON — U.S. employers added a solid 178,000 jobs in November, and the unemployment rate hit a nine-year low of 4.6 percent, though mainly because many people stopped looking for jobs and were no longer counted as unemployed.

Average hourly pay slipped after a solid gain the previous month. Pay has increased at only a modest pace in the past year.

Steady job gains and a low unemployment rate suggest that the economy is healthy. But weak pay increases and fewer Americans working or looking for work point to longer-term challenges.

Fewer than 60 percent of adults have jobs — 3 percentage points lower than when the Great Recession began in late 2007.

In part, that trend reflects retirements by the nation’s many baby boomers. But it also means hiring hasn’t kept up with population growth.

Seven years into the recovery, pay growth is still below healthy levels. And the number of part-time workers who would like full-time jobs is 28 percent higher than before the recession.

Still, nearly every economic report since the election has pointed to accelerating growth — a key reason why the Federal Reserve is considered certain to raise short-term interest rates at its next meeting later this month.

Americans bought homes in October at the fastest pace in nearly a decade. Their willingness to make such a major purchase reflects growing optimism. In fact, according to the Conference Board, Americans are more confident in the economy than at any other point in the past nine years.

They are spending more, too. Solid consumer spending helped propel growth to a 3.2 percent annual rate in the July-September quarter, the best showing in two years.

By one measure, nationwide home prices have fully recovered and are even slightly above the level they reached in 2006, before the housing bubble burst.