Scott Horsley

China is light-years ahead of the United States in doing away with old-fashioned paper money. Now China's central bank is preparing to test a digital currency. And some observers say it could mark the beginning of a new economic arms race, challenging the supremacy of the U.S. dollar.

Already, hundreds of millions of consumers in China have grown used to paying for purchases without cash, using popular smartphone apps such as WeChat and Alipay.

Job growth slowed last month as U.S. employers added just 145,000 jobs. But there was an interesting milestone in Friday's report from the Labor Department. Ninety-five percent of the net jobs added in December went to women.

Updated at 10:53 a.m. ET

Hiring slowed somewhat in December, as U.S. employers added 145,000 jobs. According to the Labor Department, that's down slightly from the three previous months, when employers added an average of 200,000 jobs. But the unemployment rate held steady at 3.5%, matching its lowest level in 50 years.

Kecia Jolley is getting a pay raise this week. But she's still making minimum wage.

Jolley works as a grocery store cashier in Missouri — one of nearly two dozen states that increased their minimum wages on Jan. 1. Economists say those mandatory wage hikes are an important factor boosting pay for workers at the bottom of the income ladder.

Jolley's Friday paycheck will be the first to reflect Missouri's 2020 minimum of $9.45 an hour, up from $8.60 last year.

"I think that I'll be better off," she says. "But I think that it's going to still be a struggle."

Before we close the books on 2019, we want to look back at some of the business stories that made headlines this year. While some were in the news for weeks — like the trade war or the strike at General Motors, which idled tens of thousands of workers — other stories came and went quickly, but not before leaving a mark on the nation's economy.

Mississippi immigration raids

Two years ago Friday, Republicans in Congress passed a sweeping tax cut. It was supposed to be a gift-wrapped present to taxpayers and the economy. But in hindsight, it looks more like a costly lump of coal.

Passed on a party-line vote, the tax cut is the signature legislative accomplishment of President Trump's first term. He had campaigned hard for the measure, promising it would boost paychecks for working people.

It took seven decades after World War II to put together a system of free trade around the world. That system has been rocked in just the past seven days.

Last Tuesday, congressional Democrats agreed to an updated trade agreement with Canada and Mexico. Three days later, China agreed to its own, preliminary trade pact with the United States.