Unusual Number of Below Asking Sales?

Naturally we keep close track of listings and sales around our two office locations -- 1715 Polk St. and 2324 Market St. -- and we post a list of sales in our office windows each month.  Here are the posters:

Market St. neighborhoods

Polk St. neighborhoods

There was something unusual that caught my eye in the November sales lists.  The percentage of listings that sold for under asking in the neighborhoods around Polk St. was approximately double around the Market St. office:  38% vs 14%.  (11 of 29 for Polk St. vs 5 of 35 at Market St.

I haven't gone back to check (I will and I'll update this post) but this seems an unusual situation from two perspectives.  First, we're used to most listings selling for over asking -- this is a city-wide phenomenon.  And more locally, although the total number of sales around each office varies from month-to-month, there are usually only a small number that sell for under asking.  Having more than a third of listings sell for under asking around the Polk St. office is very unusual.