One characteristic distinguishes the long-term unemployed from the rest of America’s jobless. It isn’t how many hours they worked at their old job, or what industry they came from, or even their level of education.

It’s bad timing.

A FiveThirtyEight analysis shows that by far the single biggest predictor of whether someone will be out of work for a year or more is the state of the economy when he or she loses his or her job.¹ Over the past 15 years, a period spanning two recessions, a one-point increase in the unemployment rate increased an individual’s odds of remaining unemployed for at least a year by about 35 percent. No other characteristic — age, sex, race, marital status, education or occupation, among others — had even close to that big an effect.

Americans who had the misfortune of losing their jobs during the height of the most recent recession in 2009 were more than four times as likely to end up out of work for a year or longer than those who lost their jobs during the comparatively good economy of 2007. Extended unemployment benefits, which are often cited as a driver of the persistently high levels of long-term joblessness, don’t appear to be a major cause of the pattern.