When it came to serial killing, Stephen Griffiths did everything by the book. He targeted prostitutes in the slums of Bradford, a city in Northern England. He chose a unique murder weapon: a crossbow. He claimed to have eaten parts of his victims—two of them cooked, one of them raw. “I’m misanthropic,” he told police investigators when he was finally caught in 2010. “I don’t have much time for the human race.” When he appeared in court, he gave his name as the “crossbow cannibal.” It was as if he’d studied up on the art of serial murder. (In fact, he had: Griffiths was a part-time Ph.D. student at Bradford University, where he was studying criminology.) And yet, for all his efforts, he got only one short blurb in the New York Times when he was sentenced last month.

Serial killers just aren’t the sensation they used to be. They haven’t disappeared, of course. Last month, Suffolk County, N.Y., police found the bodies of four women dumped near a beach in Long Island. Philadelphia police have attributed the murders of three women in the city’s Kensington neighborhood to one “Kensington Strangler.” On Tuesday, an accused serial stabber in Flint, Mich., filed an insanity plea.

But the number of serial murders seems to be dwindling, as does the public’s fascination with them. “It does seem the golden age of serial murderers is probably past,” says Harold Schechter, a professor at Queens College of the City University of New York who studies crime.

Statistics on serial murder are hard to come by—the FBI doesn’t keep numbers, according to a spokeswoman—but the data we do have suggests serial murders peaked in the 1980s and have been declining ever since. James Alan Fox, a criminology professor at Northeastern University and co-author of Extreme Killing: Understanding Serial and Mass Murder, keeps a database of confirmed serial murderers starting in 1900. According to his count, based on newspaper clippings, books, and Web sources, there were only a dozen or so serial killers before 1960 in the United States. Then serial killings took off: There were 19 in the 1960s, 119 in the ‘70s, and 200 in the ‘80s. In the ‘90s, the number of cases dropped to 141. And the 2000s saw only 61 serial murderers. (Definitions of serial murder” vary, but Fox defines it as “a string of four or more homicides committed by one or a few perpetrators that spans a period of days, weeks, months, or even years.” To avoid double-counting, he assigns killers to the decade in which they reached the midpoint of their careers.)

There are plenty of structural explanations for the rise of reported serial murders through the 1980s. Data collection and record-keeping improved, making it easier to find cases of serial murder. Law enforcement developed more sophisticated methods of investigation, enabling police to identify linkages between cases—especially across states—that they would have otherwise ignored. The media’s growing obsession with serial killers in the 1970s and ‘80s may have created a minor snowball effect, offering a short path to celebrity.

But those factors don’t explain away the decline in serial murders since 1990. If anything, they make it more significant. Then why the down trend? It’s hard to say. Better law enforcement could have played a role, as police catch would-be serial killers after their first crime. So could the increased incarceration rate, says Fox: “Maybe they’re still behind bars.” Whatever the reason, the decline in serial murders tracks with a dramatic drop in overall violent crime since the ‘80s. (One caveat: The numbers for the 2000s may skew low, since some serial killers haven’t been caught yet.)

As the raw numbers have declined, the media have paid less attention, too. Sure, you’ve still got the occasional Beltway sniper or Grim Sleeper who terrorizes a community. But nothing in the last decade has captured the popular imagination like the sex-addled psychopaths of the ‘70s and ‘80s, such as Ted Bundy (feigned injuries to win sympathy before killing women; about 30 victims), John Wayne Gacy (stored bodies in his ceiling crawlspace; 33 victims), or Jeffrey Dahmer (kept body parts in his closet and freezer; 17 victims). These crimes caused media frenzies in part because of the way they tapped into the obsessions and fears of the time: Bundy, a golden boy who worked on Nelson Rockefeller’s presidential campaign in Seattle, seemed to represent the evil lurking beneath America’s cheery exterior. Gacy, who dressed up as a clown and preyed on teenage boys, was every parent’s nightmare. “Son of Sam” David Berkowitz milked—and, in so doing, mocked—the media’s obsession with serial killers by sending a letter to New York Daily News reporter Jimmy Breslin.

The media returned the favor, inflating the perception that serial killers were everywhere and repeating the erroneous statistic that there were 5,000 serial murder victims every year. These horror stories were not exactly discouraged by the FBI, one of whose agents coined the term “serial killer” in 1981. (The phrase “serial murderer” first appeared in 1961, in a review of Fritz Lang’s M, according to the Oxford English Dictionary.) The perception of a serial murder epidemic also led to the creation of the FBI’s National Center for the Analysis of Violent Crime in 1981.

Infamous crimes almost always needle the anxieties of their periods. The murder of a 14-year-old boy by University of Chicago students Nathan Leopold and Richard Loeb in 1924 captured the growing obsession with modern psychiatry, as the pair considered themselves examples of Nietzsche’s Übermensch, unbound by moral codes. A series of child abductions in the 1920s and ‘30s, from the Wineville Chicken Coop Murders to the killing of Charles Lindbergh’s son, became a symbol of societal decay during the Depression. Charles Manson, who presided over the Tate murders in 1969, embodied a sexual revolution gone mad. The Columbine massacre preyed on parental fears of the effects of violent movies and video games.

Conversely, sensational crimes that don’t play into a larger societal narrative fade away. In 1927, Andrew Kehoe detonated three bombs at a school in Bath Township, Mich., killing 38 children and seven adults, including Kehoe—one of the largest cases of domestic terrorism before the Oklahoma City bombing in 1995. The disaster made headlines, but was soon eclipsed by Charles Lindbergh’s trans-Atlantic flight. “It was a crime that was ahead of its time,” says Schechter.

Indeed, if something like the Bath School massacre happened today, it would probably resonate more deeply than it did in the 1920s. What child abductors were to the ‘20s and serial killers were to the ‘70s and ‘80s, terrorists are to the early 21st century. After 9/11, fear of social unraveling has been replaced by anxiety over airplanes, bombs, and instant mass annihilation. Stephen Griffiths isn’t the new Jeffrey Dahmer. The Times Square bomber is.

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