Unemployment rates have fallen to very low levels in a third of U.S. states, a trend that may push up wages in those states.

The Labor Department says the unemployment rate is now significantly below the national figure of 4.7 percent in 16 states. It fell to 3.8 percent in Arkansas last month, the lowest on records from 1976.

Steady hiring has lowered unemployment rate in most states. But rates have also fallen for a bad reason: many of those out of work have stopped searching for jobs. The government doesn't count people as unemployed unless they are actively looking for work.

Employers added a significant number of jobs in just three states last month, while four states lost jobs. Employment was essentially unchanged in 43 states.