LA's average park factor for 2001-2006 is .900 and Seattle's is .883. Safeco has been (marginally) a harder place to hit for the last six years. Six years is a little subjective. LA was tougher last year (which is where I got my info), Safeco was tougher in '04, LA in 03, etc. Some date ranges favor them, and others LA. http://sports.espn.go.com/mlb/stats/parkfactor Any time frame is subjective, but going with six years is better than going with one year. Why did you pick last year instead of this year, when LA is actually the 5th best hitter's park in the league? I ignored this year for two reasons...one, I hadn't seen running park factors for '06 until I looked it up just now, and two, even if I had, this year is obviously a fluke. Park Factors shouldn't vary much from year to year, and Dodger Stadium jumped from normally being around 25 or so to 5, so something's not right there. I usually put a good amount of weight into OPS+ and ERA+, but seeing such a large variation in park factor this year, which is weighed into OPS+ and ERA+, has me doubting their validity as stats now. Nothing has changed with Dodger Stadium in the last year to justify that kind of jump that I know of, unless they moved the fences in or something of that nature that I'm not aware of.