“There are three kinds of lies: lies, damned lies and statistics.”

Benjamin Disraeli

Statistics without informed context are virtually worthless.

One can make virtually any case -- positive or negative -- by choosing a single average or median statistic relating to a short period of time and a small data set, and then cherry picking what you’re comparing today’s data to (last month, last year, or the peak of the market). Conversely, too large a data set may be misleading: the overall national trend may misrepresent California’s, and the state’s can be different from the Bay Area’s, the Bay Area’s from the city’s, and within San Francisco itself, distinct neighborhoods are often different markets going in significantly different directions.

In particular, absent some huge economic event, such as the September 2008 market meltdown, monthly fluctuations in median home sales prices are usually meaningless. Median prices often fluctuate up and down within a 5 to 10% range from one month to the next, even in stable markets.

One can only be sure market values are trending up or down if that trend is consistent over the longer term, minimally 4 to 6 months. Any definitive trend in prices and values should also be reflected in other market statistics such as average dollar per square foot, days on market, months’ supply of inventory, percentage of listings accepting offers, percentage of distress sales, and so on.

When assessing market changes calculated by computerized algorithms using very general data sets – such as Case Shiller’s or Zillow’s -- one should be clear on the details. For example, the Case Shiller Index for “San Francisco” reflects an analysis of a “metro area” comprising 5 counties with wildly varying markets (Pinole to Pacific Heights). And for the city of San Francisco, one should look at the Case-Shiller “High Tier” price Index, not the overall aggregate Index. Case-Shiller publishes NINE different home price indexes for the SF Metro Area, all of them at least slightly different, and none of them exactly applicable to any one specific property. And, quite honestly, no one actively working in real estate pays any attention to Zillow's "Zestimates" of value -- which are generally considered useless.

Always look for consistent, longer term trends across a wide range of market quantifying statistics.

DISTRESS HOME SALE can be one of two things: the sale of a bank-owned property typically pursuant to a foreclosure (also called an REO sale), or a so-called short sale, in which the seller-owner must get lender approval for a "short" payoff, a reduction in the loan amounts due on the property in order for the sale to close. These 2 kinds of distress sale are actually different animals, though both can be long, tiresome endeavors to close because one is dealing with bank bureaucracies. (In 2010 in California, about 40% of short sales fell through without closing sale.) However, in an REO sale, the seller is the bank (which may own hundreds or thousands of these properties), the property often looks "distressed" and the bank has very limited disclosure responsibilities (which is a liability to buyers). In a short sale, the seller is usually the individual owner-occupier, the property condition is and shows much better, and full seller disclosure laws apply (the buyer knows more about what he or she is buying). Both types of distress sale can be very good deals for savvy buyers and indeed investors are buying many of the REO properties around the country. But there are potentially greater risks and almost always greater hassle factors involved.

MEDIAN SALES PRICE is that price at which half the sales occur for more and half for less. It can be, and often is, affected by other factors besides changes in market values, such as short-term or seasonal changes in inventory or buying trends. Though often quoted in the media as such, the median sales price is NOT like the price for a share of stock, i.e. a definitive reflection of value and changes in value, and monthly fluctuations are generally meaningless. If market values are truly changing, the median price will consistently rise or sink over a longer term than just 2 or 3 months, and also be supported by other supply and demand statistical trends.

AVERAGE SALES PRICE is calculated by adding up all the sales prices and dividing by the number of sales. It is different from median sales price, but like medians, averages can be affected by other factors besides changes in value. For example, averages may be distorted by a few sales that are abnormally high or low, especially when the number of sales is low.

DAYS ON MARKET (DOM) are the number of days between a listing going on market and accepting an offer. The lower the average days on market figure, typically the stronger the buyer demand and the hotter the market. Note that this statistic is distorted by distress sales, which often have a very high DOM, by that minority percentage of listings that sell after multiple price reductions, and by deals that fall through after offer acceptance (the listings come back on market, but the DOM clock keeping ticking). Appealing, well-priced new listings often accept offers within 7 to 14 days of coming on market.

MONTHS SUPPLY OF INVENTORY (MSI) reflects the number of months it would take to sell the existing inventory of homes for sale at current market conditions. The lower the MSI, the stronger the demand as compared to the supply and the hotter the market. Typically, below 3-4 months of inventory is considered a "Seller's market", 4-6 months a relatively balanced market, and 7 months and above, a "Buyer's market."

DOLLAR PER SQUARE FOOT ($/sqft) is based upon the home’s interior living space and does not include garages, unfinished attics and basements, rooms built without permit, lot size, or patios and decks -- though all these can still add value to a home. These figures are usually derived from appraisals or tax records, but are sometimes unreliable or unreported altogether. All things being equal, a house will sell for a higher dollar per square foot than a condo (due to land value), a condo higher than a TIC (quality of title), and a TIC higher than a multi-unit building (quality of use). Everything being equal, a smaller home will sell for a higher $/sqft than a larger one. (However, things are rarely equal in real estate.) There are often surprisingly wide variations of value within neighborhoods and averages may be distorted by one or two sales substantially higher or lower than the norm, especially when the total number of sales is small. Location, condition, amenities, parking, views, lot size & outdoor space all affect $/sqft home values. Typically, the highest dollar per square foot figures in San Francisco are achieved by penthouse condos with utterly spectacular views in prestige buildings.

SAN FRANCISCO REALTOR DISTRICTS

District 1: Sea Cliff, Lake Street, Richmond (Inner, Central, Outer), Jordan Park/Laurel Heights, Lone Mountain

District 2: Sunset & Parkside (Inner, Central, Outer), Golden Gate Heights

District 3: Lake Shore, Lakeside, Merced Manor, Merced Heights, Ingleside, Ingleside Heights, Oceanview

District 4: St. Francis Wood, Forest Hill, West Portal, Forest Knolls, Diamond Heights, Midtown Terrace, Miraloma Park, Sunnyside, Balboa Terrace, Ingleside Terrace, Mt. Davidson Manor, Sherwood Forest, Monterey Heights, Westwood Highlands

District 5: Noe Valley, Eureka Valley (Castro, Liberty Hill), Cole Valley, Glen Park, Corona Heights, Clarendon Heights, Ashbury Heights, Buena Vista Park, Haight Ashbury, Duboce Triangle, Twin Peaks, Mission Dolores, Parnassus Heights

District 6: Hayes Valley, North of Panhandle (NOPA), Alamo Square, Western Addition, Anza Vista, Lower Pacific Heights

District 7: Pacific Heights, Presidio Heights, Cow Hollow, Marina

District 8: Russian Hill, Nob Hill, Telegraph Hill, North Beach, Financial District, North Waterfront, Downtown, Van Ness/ Civic Center, Tenderloin

District 9: SoMa, South Beach, Mission Bay, Potrero Hill, Dogpatch, Bernal Heights, Inner Mission, Yerba Buena

District 10: Bayview, Bayview Heights, Excelsior, Portola, Visitacion Valley, Silver Terrace, Mission Terrace, Crocker Amazon, Outer Mission

Some Realtor districts contain neighborhoods that are relatively homogeneous in general home values, such as districts 5 and 7, and others contain neighborhoods of wildly different values, such as district 8 which includes both Russian Hill and the Tenderloin.

Median and average statistics are generalities subject to fluctuation due to a variety of reasons (besides changes in value): how they apply to any specific property is unknown. Averages may be distorted by one or two sales substantially higher or lower than the norm, especially when sample size is small. Sales not reported to MLS – such as many new-development condo sales -- are not included in this analysis (except in the specific chart on the SF new-development condo market). All figures should be considered approximate and are derived from sources deemed reliable, but may contain errors and omissions, and not warranted. We are happy to provide or direct you to the original data upon which each chart is based.