With a month left in 2017 and homicides and shootings continuing to plummet, NYPD officials are confident the city will record fewer than 300 killings by year’s end — a level last seen in the waning days of World War II, according to police records and law enforcement sources.

Through Nov. 29, the NYPD has tallied 258 homicides, compared with 309 in the same period in 2016, a drop of 16.5 percent. Shootings have totaled 732 compared with 932 in 2016, a drop of 21.4 percent.

The city’s falling homicide rate has been the topic of discussion around the country among criminologists and law enforcement experts.

“Two hundred and fifty eight, that means that the 12-month total in all probability will be under 300,” said noted criminologist Franklin Zimring, who teaches at the UC Berkeley School of Law. “You can do better than that but you will be in Montreal.”

NYPD spokesman Stephen Davis agreed that the numbers appear to show the downward homicide trend continuing through at least Dec. 31.

“Although we never like to make firm projections,” Davis said Thursday, “looking historically and how the year is shaping up, we are track for the 300 number.”

Chief Dermot Shea, head of NYPD crime strategies, said the new crime lows are the result of the city reaping the benefit of several years of changing tactics, including a focus on gun crimes and gang activity.

“It is not a surprise, but there is not a day of rest, even with the success we have had,” Shea told Newsday.

NYPD officials have generally been cautious about predicting absolute numbers of killings because the possibility exists for a catastrophic event like the Halloween terrorist attack that killed eight people. Barring such an outbreak of bloodshed, the falling homicide rate could lead to the city recording just over 280 killings in 2017, officials said.

Whichever comparative benchmark is used, such a low level would be historic.

In 1994, the year modern Compstat record-keeping began, the city had 1,561 homicides. Historically, police officials said, the consistent method of recording homicides began in the early 1960s when killings numbered on average about 500 annually. Although it was unclear exactly how homicides were counted in World War II, police data showed 292 killings in 1945.

While NYPD officials chalk up the decline to current gang initiatives, Zimring said getting at the root cause of the unprecedented crime declines in the city will take more study.

“It is wonderful news but it is in the area of causality where there is great mystery,” said Zimring, author of a book about the city’s historic crime decline.

Like many experts, Zimring has said that in the past, there had to be a bottoming out to crime, particularly homicides, in New York City. But current trends have made the crime cellar difficult to reach.

“Is there a stopping point, probably yes, but we don’t know enough about that dynamic yet,” Zimring said.