WASHINGTON – Four states — California, South Carolina, Michigan and Rhode Island — registered unemployment rates above 10 percent in January, and the national rate is expected to hit double digits by year-end.

The U.S. Labor Department's report on state unemployment, released Wednesday, showed the increasing damage inflicted on workers and companies from a recession, now in its second year. Some economists now predict the U.S. unemployment rate will hit 10 percent by year-end, and peak at 11 percent or higher by the middle of 2010.

In December, only Michigan had a double-digit jobless rate. One month later, four states did and that doesn't count Puerto Rico, which saw its unemployment rate actually dip to 13 percent in January, from 13.5 percent in December.

California's unemployment rate jumped to 10.1 percent in January, from 8.7 percent in December, as jobs have disappeared in the construction, finance and retail industries.

Michigan's jobless rate jumped to 11.6 percent in January, the highest in the country. The second-highest jobless rate was South Carolina at 10.4 percent. Rhode Island was next at 10.3 percent, which marked an all-time high for the state in federal records dating to 1976. California rounded out the top four.

Forty-nine states and the District of Columbia registered unemployment rate increases. Louisiana was the only state to record a monthly drop. Its unemployment rate fell to 5.1 percent in January from 5.5 percent in December.

The U.S. unemployment rate, released last week, rose to 8.1 percent in February, the highest in more than 25 years.

Employers are laying off workers, holding hours down and freezing or cutting pay as the recession eats into sales and profits.

Disappearing jobs and evaporating wealth from tanking home values, 401(k)s and other investments have forced consumers to retrench, driving companies to shrink their work forces. It's a vicious cycle in which all the economy's problems feed on each other, worsening the downward spiral.

And more layoffs are on the way. National Semiconductor Corp. said Wednesday it will lay off 1,725 employees, more than one-quarter of its work force, after third-quarter profits fell 71 percent.

Industrial conglomerate United Technologies Corp., which makes Otis elevators and Sikorsky helicopters, said Tuesday it will lay off 11,600 workers, or 5 percent of its work force. Dow Chemical Co. on Monday said it would cut 3,500 jobs at chemical company Rohm & Haas Co. as part of its $15 billion buyout of the company.

President Barack Obama has urged Americans to be patient, saying it will take time for his economic revival and job-creation programs to bear fruit.

Obama is counting on a multipronged assault to lift the country out of recession: a $787 billion stimulus package of increased federal spending and tax cuts, a revamped bailout program for troubled banks and a $75 billion effort to stem home foreclosures.

Nationwide, the recession has claimed a net total of 4.4 million jobs since December 2007, and has left 12.5 million people searching for work — more than the population of Pennsylvania.

The state unemployment report also showed that North Carolina and Oregon — along with South Carolina — notched the biggest monthly gains of 1.6 percentage-points each.

North Carolina's rate soared to 9.7 percent in January, from 8.1 percent in December, while Oregon jumped to 9.9 percent, from 8.3 percent.

Meanwhile, Georgia's jobless rate climbed to 8.6 percent in January, an all-time high on federal records.

On a brighter note, Wyoming continued to register the lowest unemployment rate — 3.7 percent.