For days after Richard Matt and David Sweat’s June 6 escape from the Clinton Correctional Facility in Dannemora, New York, there seemed to be little concrete evidence of where they were. Reports had them heading toward Vermont or perhaps Canada. Then they were thought to be near the Pennsylvania border. As hundreds of law enforcement officers combed through roads and fields and forests, Matt and Sweat stayed out of sight.

Monday’s discovery of DNA belonging to both men in a cabin only about 25 miles from the prison—DNA seemingly just a few days old—suggests that police may be getting closer to them. That’s very different from having the two men in hand. But statistics on prison escapees suggest that Sweat and Matt will have a very hard time avoiding recapture—though if they make it past the first month, their odds seem to improve.

As with so many criminal-justice issues in the news this year, there aren’t reliable, comprehensive statistics on prison escapes. But Richard Culp, a professor at the John Jay College of Criminal Justice, surveyed the available data in 2005 and came up with some useful context. Combing various calculations and data sets, Culp calculated that about three-quarters of all escaped inmates were recaptured. Break those numbers out and the figures get even less favorable for Matt and Sweat: More than 92 percent of fugitives from medium- and high-security prisons were captured within a year (compared to less than 70 percent of work-release escapees). And that estimate is conservative.

Surely, though, the chances of escape must improve over time? Perhaps: The longer fugitives are out of hand, the farther away they can get, the better they disguise themselves, and the less the media covers them, decreasing the chance a vigilant citizen will spot and report them. (Many of the U.S. Marshals’ 15 most wanted have been on the lam for a very long time, such as Raymond Abbott-Baerga, who escaped a maximum-security prison, amid a hail of gunfire, in 1992.)

In a separate 2005 paper, Culp and Elizabeth Bracco looked at how quickly escapees were captured, and found that most were snagged within the first 24 hours after escape. Nine out of 10 of those who were caught were collared within the first month:

Time Until Prison Escapees Were Captured

Time of capture Frequency Percentage Cumulative
Within 1 hour 7 9.6 9.6
Within 1 day 36 49.3 58.9
Within 1 week 15 20.5 79.4
Within 1 month 6 8.2 87.6

Data: Culp and Bracco. Created with the HTML Table Generator

Chuck Jordan, president of the National Association of Fugitive Recovery Agents, estimated the magic number for escapees as being six months. After that, he said, “the fugitive has had a chance to acclimate to life on the run, establish a life somewhere, or establish a low profile. The long-term fugitive, who’s on the run for years—they tend to settle down. Some of these people have become well-regarded in the communities where they’re at.” Sometimes they get brazen: Jordan had heard of a fugitive who was caught after more than 20 years when he ran for local city council. And Jordan noted that law-enforcement agents had an edge over those who pursue a typical bail-jumper, since authorities knew within hours of the escape that Matt and Sweat were missing.

More successful escapes are rare, but not unheard of. In May, an Akron, Ohio, man made headlines after he was captured by U.S. marshals in Florida. Frank Freshwaters, who was 79, had escaped a prison farm in Sandusky in 1959 and managed to elude capture for decades.

Just how common is escape from prison? The Associated Press set out to figure out how many escapees there are on the loose right now and struggled to fully resolve the question. As its report noted, the Bureau of Justice Statistics tallies about 2,000 escapees in 2013, but some of those are people who left minimum-security prisons or disappeared while on work release. The AP surveyed states and came up 224 escapees; that number is incomplete, but also includes some fugitives who are almost certainly dead by now. If that 2,000 number is right, it’s a serious decline from the 1990s. For 1997, for example, Culp found estimates ranging from 4,500 to 8,500.

In some ways, Sweat and Matt are atypical fugitives. Not only have they been on the lam much longer than average, but most escapees are not violent offenders (both the New York escapees are murderers); Matt is older than the typical escapee; and of course, it’s very difficult to escape from a maximum-security prison. Like most escapees, however, both are white and male.

Often, escapees depend on finding and exploiting weaknesses in staffing at a facility, as Matt and Sweat seem to have done. (Culp records one particularly humiliating case for authorities in which an inmate who was enlisted to role-play an escapee during a dog-training exercise slipped away.) But few escapes involve a sophisticated plan, as Matt and Sweat’s did, and few depend on the assistance of corrections staff, as they allegedly did by relying on Joyce Mitchell.

Now, however, Matt and Sweat may be out on their own, while hundreds of police with night-vision binoculars, dogs, and helicopters scour New York for them. Chuck Jordan said he didn’t expect them to escape the cops permanently. “They’ve got to be lucky every day, and law enforcement only has to get lucky once,” he said. “Their time is going to run out.”