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'Pink slip stigma' stronger the longer you don't have a job

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For the 5 million long-term unemployed, defined as those out of work for 27 weeks or more, it doesn't look pretty.

Call it "pink slip stigma." When you don't have a job, it's harder to convince a new employer to give you one. And we all know the longer you're out of the game, the harder it gets. What we didn't know was exactly how hard. Now, thanks to some sneaky economists, using 12,000 fake resumes, there's some solid data.

A team of researchers sent out over 12,000 fake resumes to over 3,000 online job postings. They designed the resumes so that the candidates were all equally qualified. The only thing they changed was the length of time the fictional candidate was out of work.

For the 5 million long-term unemployed, defined as those out of work for 27 weeks or more, it doesn't look pretty.

"The labor market penalizes you for being out of work," Kory Kroft, co-author of the study "Duration Dependence and Labor Market Conditions: Theory and Evidence from a Field Experiment," published by the National Bureau of Economic Research, told NBC News. 

From 0-6 months, the percentage of callbacks gradually declines from about 7 percent. But once it hits 6-8 months there's a steep drop-off. After 6 months of being jobless, there's only a 4 percent chance you'll get called in for an interview, a 45 percent plummet.

What gives? Well, "There's two kinds of employees, productive and unproductive," said Kroft. "Firms will use the number of months you've been out of work as a "proxy" or "signal" of how productive you are."

The idea is that when you're out of work, your job is getting a job. If you're not great at that job, you might not be great at the one the employer is hiring for. And the effect is greater the longer you've been out of work.

One bright spot, if you can call it that, is that after 8 months the "pink slip stigma" levels off. So if you're sitting on a chair in a lobby waiting for a job interview next to a guy out of work for 14 months and you've been without a job for 34, he doesn't have any better shot than you just based on that fact alone.

So what advice is there for job-seekers? For one, check out the odds of getting a callback in response to an online job posting. You have a 93 percent chance of your resume getting deleted. That's a pretty strong testament to how you don't want to just blast out resume after resume in response to Monster.com posts. Chat up friends and colleagues, go to networking events, and look for ways to make human, in-person connections to get you your next gig.

And if you're going to wallow in self-pity, make it quick. "Hit the ground hard early on," after losing a job, says Kroft, an Assistant Professor of Economics at the University of Toronto.

Better yet, pay attention to common signals that you could be up for getting pushed out - like overall company layoffs, being left out of email chains and meetings, and people giving you pitying looks in the hallways - and start your job-search before you get called into HR.

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