WASHINGTON (MarketWatch) - The U.S. gained a whopping 312,000 new jobs in December to bring total employment gains in 2018 to a three-year high of 2.64 million. Economists polled by MarketWatch had expected a gain of 182,000 nonfarm jobs. The unemployment rate rose to 3.9% from a 49-year low of 3.7%, largely because more people entered the workforce in search of jobs. The average wage paid to American workers climbed 11 cents, or 0.4%, to $27.48 an hour, the Labor Department said Friday. The 12-month rate of hourly wage gains edged up to 3.2% from 3.1%, matching a postrecession high. Hours worked each week increased 0.1 hour to 34.5 hours. The government said 176,000 new jobs were created in November instead of 155,000. October's gain was raised to 274,000 from 237,000.