Pretty well it turns out. According to the CDC, Portland's annual firearm homicide rate of 2.2 per 100,000 (2006-2007 data) is one of the lowest among the largest 62 cities in the US, which average 9.7 per 100,000. The only other similar sized cities that are close are San Jose, which is lower at 1.5, and San Diego, which is a bit higher at 2.8. So, in general, Portland has a very low incidence of firearm homicide which makes the recent killings no less tragic or infuriating, but does provide some perspective.
The extreme case, by the way is absolutely horrifying: New Orleans has a firearm homicide rate of 62.1, almost 30 times higher than Portland's. At what point, I wonder, does the federal government step in and take over the completely ineffectual police force?
Things aren't all rosy for Portland (no pun intended) in terms of firearm deaths. Portland is actually well above average in terms of firearm suicide where the 62 city average is 4.7 per 100,000 but Portland's is 6.4 (San Jose is 2.1 and San Diego is 4.3 by comparison).
I leave you with some interesting notes on the data from the CDC:
Although firearm homicide rates tended to be higher with increasing urbanization and among youth relative to persons of all ages, this was not the finding for firearm suicide rates. The 50 largest MSAs collectively had an annual all-ages firearm suicide rate of 5.0 per 100,000 persons aged ≥10 years, and 52% of these MSAs (26 of 50) had rates lower than the national rate of 6.5. Central cities within these MSAs collectively had an annual all-ages firearm suicide rate of 4.7, and 55% of these cities (27 of 49 cities with reportable all-ages firearm suicide statistics) had rates lower than those of their MSAs. Youth firearm suicide rates were comparatively low, with a composite rate of 1.3 for the 50 largest MSAs and an identical composite rate of 1.3 for their central cities. Males accounted for more than 87% of firearm suicides (ages ≥10 years) nationally and for all MSAs collectively.
Notable patterns by geographic region were observed. All-ages firearm homicide rates generally were higher for MSAs in the Midwest (seven of 10 above the median MSA rate of 5.4) and South (13 of 21 above the median rate) than for MSAs in the Northeast (six of seven below the median rate) and West (eight of 12 below the median rate). All-ages firearm suicide rates were generally higher for MSAs in the South (15 of 21 at or above the median MSA rate of 6.3) than for MSAs in the Northeast (six of seven below the median rate), Midwest (six of 10 at or below the median rate), and West (seven of 12 below the median rate); the highest rates were concentrated in the South and West.
During 2006--2007, firearm suicide and firearm homicide were the fourth and fifth leading causes of injury death in the United States, respectively. For youths aged 10--19 years, firearm homicide was the second leading cause and firearm suicide was the fifth leading cause of injury death nationally. The statistics presented in this report indicate that firearm homicide rates were higher and firearm suicide rates were lower among residents of the 50 largest MSAs compared with the nation as a whole; residents of these MSAs represented 54% of the U.S. population during 2006--2007, but accounted for 67% of firearm homicides and 41% of firearm suicides nationally. Similarly, for youths aged 10--19 years, residents of these MSAs accounted for 73% of firearm homicides and 39% of firearm suicides nationally. More than 85% of violence-related firearm deaths occurred among males, both nationally and for the 50 largest MSAs collectively.
Note that the statistics given above are for the City of Portland and other cities proper. The statistics for MSA's can be found by following the link.