(Bloomberg Business) -- Be patient, job seekers: It's takingmuch longer to get hired in the U.S.

Candidates had to wait about 22.9 days for an offer or rejectionin 2014, up from 12.6 days four years earlier, according to surveydata from online job-search network Glassdoor Inc.

The longer wait time is largely due to a rise in the use ofbackground checks for jobs, which have gotten cheaper toconduct, "as a proxy for judgment and quality of candidates forjobs" across fields, said Andrew Chamberlain, Glassdoor'schief economist.

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The data show that government agencies, which typicallyencounter more regulatory hurdles in hiring and often conductbackground checks before adding staff, take the longest to closethe deal.

Those averaged a 60-day wait, helping to explain why Washingtonblew other U.S. cities out of the water in this dubioussuperlative: The average duration was 34.4 days in the nation'scapital, more than nine days longer than the second-longest,Portland, of 25 of the biggest samples.

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Joining D.C. near the top were several tech-centric cities:Seattle, San Jose and San Francisco.

Those represent a more fundamental shift in the U.S. labormarket toward "more high-tech, more non-routine, morejudgment-oriented jobs," such as software engineers and datascientists, Chamberlain said. "Those things definitely take longerto tease out whether someone's a good candidate or not."

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The Glassdoor data offer another look at how efficientlythe job market is matching employers with job-seekers. Thenumber of private-industry job openings outpaced the number ofworkers who were hired in April, a first in Labor Department databack to December 2000.

Only 1.6 people are now vying for every job opening, comparedwith about 1.8 when the last recession began in December 2007.

While more job openings don't implicitly sound like a bad thing,the relative lag in getting unemployed Americans in those roles haseconomists questioning whether something has changed since therecession.

The relationship between job openings and the unemployment rateused to be a lot easier to decipher, back in the good ole days whenhiring was proving more efficient. Now, the Beveridge Curve thatplots these indicators has shifted into uncharted territory,showing that employers have been reluctant to close the deal evenas they're asking for more workers.

Indeed, more small-business employers were finding a hard timefilling job openings in May than at any time since April 2006,according to survey data from the National Federation ofIndependent Business.

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