It was the second straight month the rate dropped.
The number of unemployed people fell by 600,000 to 13.9 million, the bureau said.
The economy added only 36,000 jobs during the month but the bureau sharply revised its job gains in November -- from 39,000 to 71,000 -- and October -- from 172,000 to 210,000. In December, the economy added 130,000 jobs, 27,000 more than was previously reported, the bureau said.
The bureau said hourly earnings rose 0.4 percent in January or by 8 cents per hour.
In January, manufacturing firms added 49,000 jobs and healthcare gained 11,000. Retail companies added 28,000 and construction jobs shrank by 32,000. Transportation and warehousing jobs also declined, down 38,000 for the month. Professional and business service jobs declined by 11,000, but 25,000 temporary jobs were added in the month.
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