Did your last set of job interviews go on forever ?

In the U.S., the average job interview process now takes 23 days - almost double the time it took five years ago.

The job interview process is taking longer, and it's not because companies have tons and tons of candidates. In fact, as the economy improves, the opposite is supposed to be happening: more jobs with less competition.

Blame regulations and the difficulty in firing someone after you hire them. That's the consensus of analysis of over 340,000 "interview reviews" by job candidates on Glassdoor.com. "Laws that make it more costly to hire and fire workers affect the speed and efficiency of job matching," wrote Glassdoor chief economist Andrew Chamberlain.

Glassdoor said the average job interview process in the United States now takes 23 days, almost double the time it took five years ago.

It's not just a U.S. thing, either. "The trend appears in North America, parts of Europe and into Australia, even after controlling for differences in job titles, companies, industries and several other factors," said Chamberlain. The longest delays are in France, where the average interview process takes over a month. "This partly reflects differences in labor market regulations, culture and other institutions such as rates of unionization."

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Chamberlain said he believes longer hiring times cost companies money as jobs go unfilled. He puts some of the blame on human resources departments, which employ an ever-expanding arsenal of interviewing techniques.

Here's what changed in five years:

Five years ago, 1 in 4 job candidates were subjected to a background check, according to Glassdoor. That number is now closer to half. Several other types of screening have risen at least 50 percent since 2010, including skills tests, drug tests and personality tests. Those can add a full week to the process.

"Unlike industry or geographic factors, the choice of which and how many interview methods to employ can be directly influenced by company hiring managers," Chamberlain said. By providing specific estimates for each screening process-up to eight days for telephone interviews, six days for panel interviews-companies can figure how much time and money is being spent and try to create a more efficient process.

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If it's good enough for government work, you're going to have to wait for it. Glassdoor reports that getting hired by the U.S. government now takes two months on average. Perhaps that's why Washington has the longest interview process of any major metropolitan area. Not far behind, however, are tech hubs like San Jose (25 days) and San Francisco (24 days). On the other hand, the average hiring process in Miami only takes 18 days.

Understandably, some jobs take longer to fill. Being hired as a police officer takes four months. However, the second longest hiring process is for patent examiners (88 days-almost three months), followed by assistant professors (59 days). At the other end of the hiring spectrum, it takes only three weeks to be hired as a software engineer, eight days to be hired as a model (the same length as a data scientist) and six days as a bartender.

According to Glassdoor, there's no difference in how long it takes to get hired based on whether candidates are male or female, black or white, bachelor's or master's. "Personal characteristics of job seekers-including gender, age and highest level of education-have zero statistical effect on interview lengths."

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