FILE - In this Thursday, Nov. 14, 2013, file photo, retired U.S. Air Force Master Sgt. Thomas Gipson, of Atlanta, right, has his resume looked over by Ralph Brown, a management and program analyst with the Centers for Disease Control and Prevention, during a job fair for veterans at the VFW Post 2681,Marietta, Ga. The government reports on state unemployment rates for March on Friday, April 18, 2014. (AP Photo/David Goldman, File)

WASHINGTON (AP) -- More than two-thirds of the states reported job gains in March, as hiring has improved for much of the country during what has been a sluggish but sustained 4 1/2-year recovery.

The Labor Department said Friday that unemployment rates dropped in 21 states, rose in 17 and were unchanged in the remaining 12. Meanwhile, hiring increased in 34 states and fell in 16.

The unemployment rate varies from as low as 2.6 percent in North Dakota to as much as 8.7 percent in Rhode Island. South Carolina has experienced the sharpest rate decline over 12 months to 5.5 percent from 8 percent.

The rate nationwide stayed at 6.7 percent in March for the second straight month. That national rate stayed flat because someone was hired for almost every person who entered the job market last month.

Employers added 192,000 jobs nationwide in March, close to the average monthly gains of the past two years.

Ohio experienced the largest month-to-month drop in its unemployment rate: 0.4 percentage points to 6.1 percent. That steep drop occurred because the state added 12,000 jobs last month, while the total number of people in its job market fell 11,200 to 5.75 million.

Unemployment rates can fall when people leave the job market, as well as when employers hire.

North Carolina reported the second largest year-over-year drop in the unemployment rate: a 2.2 percentage point decrease to 6.3 percent. Part of that decline came from the loss unemployment benefits for jobless workers. Because those workers needed to look for jobs in order to receive benefits, the loss of the jobless aid likely caused them to give up their hunts and no longer be counted as unemployed.

Several states continue to lag the gains made across the country. Unemployment remains elevated in Nevada (8.5 percent), Illinois (8.4 percent), California (8.1 percent) and Kentucky (7.9 percent).