The percentage of rape cases Portland police marked as "cleared" in 2016 was the eighth-lowest in the United States among 64 cities with a population of more than 300,000, according to data made public this month by ProPublica.

The Portland Police Bureau received 396 reports of rape in 2016, the most recent year available for study. They "cleared" just 53 of those cases—or 13 percent—meaning they identified a suspect and had sufficient evidence to make an arrest. Just 25 cases, or 6 percent, resulted in arrests.

Portland police spokesman Sgt. Chris Burley says the bureau uses a "victim-centered" approach to solving rape cases, so the bureau will often delay or suspend investigations until a victim wants to cooperate with police. He also says PPB does not declare cases cleared if officers cannot solve them—a tactic some departments use.

The bureau still has a long way to go to catch up to national leaders like Suffolk County Police Department in New York, which made arrests in 81 percent of the rapes reported in 2016. Here's how Portland compared to five similarly sized cities.