WASHINGTON — U.S. employers added a modest 199,000 jobs last month while the unemployment rate fell sharply, at a time when businesses are struggling to fill jobs, with many Americans remaining reluctant to return to the workforce.

The Labor Department also said Friday that the nation's unemployment rate fell to a healthy 3.9% from 4.2% in November. Though unemployment continues to fall, the U.S. in December added jobs at a slower rate than it did in November, when the economy added 210,000 jobs.

Speaking at the White House Friday, President Joe Biden said the report marked a "historic day," noting that the unemployment rate fell below 4%. He noted that it marked the sharpest single-year decline in unemployment in U.S. history.

However, the report fell short of analyst projections. CNBC reports that forecasters expected the U.S. had added 422,000 jobs in the month of December.

Though the highly-contagious omicron variant of COVID-19 began spreading the U.S. in December, CNBC spoke to forecasters that said the new strain likely did not have an impact on Friday's report. However, omicron will likely play a major role in January's job report, which will be released early next month.

Friday's report comes just days after a separate report found that more Americans than ever quit their jobs in the month of November. Biden said during his remarks Friday that more Americans are simply transitioning to new opportunities.

"Americans are moving up to better jobs with better pay, with better benefits," Biden said.

The Dow Jones Industrial Average is on the rise Friday following the release of the December jobs report.

Data released from the Labor Department showed the U.S. economy lost 140,000 jobs in the month of December, and it appears women accounted for all of the job losses.

For the month of December, the data show men overall gained 16,000 jobs, while women lost 156,000, for a total loss to the economy for that month of 140,000.

Not just women, minority women. The data shows Black and Hispanic women lost jobs in December, while white women gained. In December, Hispanic women have the highest unemployment rate at 9.1%, followed by Black women at 8.4%, with white women at 5.7%. The data does not break out other racial or ethnic identities in unemployment rates.

Overall, the unemployment rate in this country in December was 6.7%.

For months, analysts and economists have been pointing to the number of women leaving the workforce, for two main reasons. Women, and especially women of color, disproportionately work in some of the hardest-hit areas of the economy like retail, restaurants, education and hospitality.

Second, women have been more likely than men to leave a job to stay home with kids who are remote learning or whose daycare has closed.

"Those sectors are less likely to have flexibility, so when employers are inflexible or women can't come to work because of caregiving responsibilities — they have to exit the workforce," C. Nicole Mason, president and CEO of the Institute for Women's Policy Research, told CNN.

December’s Labor statistics were a blow to the economy, after analysts had expected small gains the report showed a huge drop. This was the first time since April that U.S. employers overall cut jobs.

In April, 22 million jobs were cut, and according to the December jobs report, the economy still has 9.9 million fewer jobs than it did before the pandemic.

Of those 9.9 million jobs that have not returned since February, the Labor Department says roughly 5.4 million were held by women and 4.4 million were held by men.