Officials said Wednesday that homelessness in New Orleans and Jefferson Parish declined by 9 percent in January compared with a year earlier, while the number of people described as “chronically homeless” dropped by a little more than half.

That decline bucked the national trend. Across the U.S., homelessness ticked upward last year for the first time since 2010, climbing nearly 1 percent as the number of people without shelter exploded in big West Coast cities like Los Angeles.

Martha Kegel, who leads a coalition of local groups that fights homelessness called Unity of Greater New Orleans, attributed the big drop in the number of chronically homeless — defined as those with mental or physical disabilities — to a concerted push during the final months of last year to find permanent housing for more people.

“We’re determined to bring the number of chronically homeless people down as close to zero as possible by the end of this year,” she said during a news conference Wednesday.

Kegel also reported some “not so good news,” including a “high inflow” of newly homeless people, though she did not put a number on that phenomenon.

She also cited a stubbornly high proportion of homeless people in Orleans and Jefferson — 50 percent — who remain exposed to the elements at night rather than sleeping in shelters, a “much higher” proportion than in many big American cities, she said.

She said the No. 1 reason people continue falling into homelessness in the region is the rising cost of rent.

“People tend to focus on the frailties of the homeless population, and it’s true that many homeless people do have mental illness, do have substance abuse disorders, do have severe physical disabilities,” she said. “But the primary driving factor is a lack of affordable housing.”

Overall, the number of homeless people counted in the two parishes in January came to 1,188, compared with 1,301 the year before, according to Unity. That figure was down 90 percent from a peak in 2007, when homelessness had been badly exacerbated by the destruction that followed Hurricane Katrina.

The number of chronically homeless dropped by 52 percent, down to 193 in January compared with 404 a year earlier. That figure was down 96 percent from 2009.

The number of homeless families was down 28 percent, which Unity attributed to a new campaign to speed up the pace of finding permanent family housing.

The group also said that officials had managed to keep the rate of homelessness among military veterans at “functional zero” for the third year in a row, meaning that newly homeless vets are placed in permanent housing in an average of 30 days after they are identified.

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