A pit bull participates in a U.S. Postal Service dog bite prevention event in Los Angeles. (Amanda Lee Myers/AP)

Robert Rochester, a 55-year-old postal worker, was delivering mail in Stanton, Del., late one afternoon when a German shepherd charged out from a nearby yard and pounced on him.

The fully grown dog mauled Rochester’s legs, arm and stomach before a passing motorist pulled Rochester into her vehicle. Badly injured, Rochester died several days later of cardiac arrest as a result of his wounds, news outlets reported.

Though most canine encounters don’t end so tragically, the attack on Rochester, which happened in 2012, is all too familiar for the country’s roughly 329,000 letter carriers. And while the image of an ill-tempered dog chasing a terrified mail carrier may sound like a made-for-TV cliche, new statistics show that the menace is as real as ever.

The U.S. Postal Service on Thursday released a report showing 6,755 postal employees were attacked by dogs in the 2016 calendar year — a jump of more than 200 from the year before and, as the Associated Press reported, the highest number recorded in three decades.

“It’s always on your mind as a carrier, ‘Is there a dog in the area and is it a threat?’” James Solomon, a postal worker of 17 years, told the Associated Press.

The figures were published in advance of National Dog Bite Prevention Week (yes, that exists), and they represent a serious problem for letter carriers that’s unlikely to go away anytime soon.

For at least five years, the number of employees attacked annually hovered between 5,500 and 5,900. But the figure has climbed steadily since 2013, when 5,600 employees were attacked, USPS statistics show. The last time attacks were so high was the 1980s, when there were more than 7,000 in a single year, according to the Associated Press.

The reason for the jump is unclear, but there’s no denying it coincides with a boom in online retail sales in recent years. Major retailers such as Amazon.com and Target have experienced surges in online business, particularly during the holiday season, with more people opting for home delivery over storefront shopping, as The Washington Post has reported. (Jeffrey P. Bezos, the chief executive of Amazon, owns The Post.)

For postal workers, more online sales mean more package deliveries, which have increased by about 1.5 billion since 2010. And more deliveries, of course, means more exposure to household pets, some of which aren’t exactly welcoming.

According to the USPS, it’s not uncommon for dogs to view postal workers handing mail to their owners as a threatening gesture.

“Even good dogs have bad days,” said U.S. Postal Service Safety Director Linda DeCarlos in a statement on Thursday.

Los Angeles topped the list of U.S. cities with the most dog attacks, with 80 postal workers reporting having been bitten there last year, according to the USPS. Other large cities such as Houston and Chicago appeared in the top 10, but so did smaller cities such as Cleveland, which ranked third with 60 attacks, and Louisville, which ranked fifth with 51.

Nationwide, about 4.5 million dog bites are reported every year, according to the Centers for Disease Control and Prevention.

Dog attacks on postal workers have been a persistent problem in Los Angeles, which has appeared at or near the top of the list in previous years. In 2015, NPR profiled a letter carrier who had been bitten three times and chased many more during his 20-year career. That year, USPS reported, 74 letter carriers were attacked in Los Angeles. In response, the city’s postmaster enlisted the help of a major dog training franchise to teach employees and pet owners how to prevent attacks, as NPR reported.

The USPS says it’s taking similar steps to keep its employees safe, urging dog owners to tell letter carriers about their pets. As DeCarlo, the safety director, said of a previous year’s findings: “There’s a myth we often hear at the Postal Service: Don’t worry — my dog won’t bite.”

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