Six states -- including California, New York, Texas and Ohio -- can only fund up to 10 weeks of benefits before they'll have to turn to the federal government or other sources for infusions, according to a recent estimate from the Tax Foundation. Another 15 state trust funds don't meet the federal Department of Labor's recommended minimum solvency standard, which requires being able to pay benefits for a year in an economic downturn similar to the Great Recession.

The cash crunch won't affect the millions of Americans currently applying for or receiving benefits -- they'll get their weekly checks regardless of their state's financial situation. About 16.8 million people , roughly 11% of the labor force, filed initial unemployment claims over three weeks ending April 4 -- dramatically higher than during the Great Recession. Economists expect job losses to continue.

But states do remain responsible for their share of unemployment insurance, which typically lasts up to 26 weeks. If their trust funds run out, they could take loans from the federal government -- but some states could wind up paying interest and employers could face heftier taxes to cover the debt. Other choices: Issue bonds or draw down other state funds, which most can ill-afford to do as the coronavirus wreaks havoc on tax revenues.

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