The number of people living in unsheltered homes in Seattle and King County increased by about 19 percent over last year.

The number of unsheltered homeless is 4,505, according to Friday’s One Night Count.

Last year’s count showed a 21 percent jump in the number of unsheltered homeless, with 3,772 men, women, and children counted on the streets alone. More than 3,200 people were counted in shelters, while 2,993 individuals had transitional housing.

Related: A look at Seattle’s homeless ‘Shacktown’ history

After the count, Seattle Mayor Ed Murray said there needs to be better data on homeless.

“We need to do a better job later on understanding what are the issues that cause people to end up on our sidewalks and in tents along our freeways,” he said. “We need better data.”

The number of households returning to homelessness after exiting permanent housing was 12 percent. That’s down from 2014, when 16 percent returned to homelessness, according to Seattle University’s Project on Family Homelessness and the All Home.

Of those counted, 35.6 percent were “mentally ill,” and 9.6 percent were veterans. And of those counted, more than 2,000 are under the age of 17, according to Seattle University and All Home. About 400 families are living in places not meant for human habitation.

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