>In Seattle, prosecutors and law enforcement recently estimated that the majority of the region’s homeless population is hooked on opioids, including heroin and fentanyl.... For the unsheltered population inhabiting tents, cars, and RVs, the opioid-addiction percentages are even higher—the City of Seattle’s homeless-outreach team estimates that 80 percent of the unsheltered population has a substance-abuse disorder. Officers must clean up used needles in almost all the homeless encampments.
Might be a difference in wording. As I recall, 2/3 of Seattle homeless are not sleeping on the street (instead they are in cars or shelters), which may make them "sheltered". The other 1/3 are in the street and if most of them are addicts, then yes, about 1/3 of total homeless are addicted as well
