Any one zip code generally has too few sales to draw any conclusions, PLUS there is usually a wide difference in days on market between short sales, bank owned, and "traditional' sales, Here are the numbers for 97210 for July:
Traditional Sale, 6, 52 Days on Market
REO - last sale was in June 1 sale, 153 Days of Market
Short Sale - None since 12/2010
Traditional Sale, 10 Sales, 130 Days on Market
REO - 2 sales, 101 Days on Market
Short Sale - 1 sale, 126 Days on Market.
If you want to consider the entire Portland Tri-county Area, Days on Market
Traditional Sales - 129
REO - 72
Short Sale 173
Traditional - 96
REO - 64
Short Sale 197
I'd be happy to help you with other figures, but I think you see that one zip code doesn't produce meaningful results.