This month we tackle a favorite topic: $1 million-plus housing in San Diego. That might be seen as an oxymoron in this pricey market, but not really so. The median price of a detached home here is about $600,000, so there are really a lot of homes priced below seven figures.

As might be expected, most of those $1 million-plus homes and condominiums sold — about 15 percent of the total last year — are in the revered 92037 (La Jolla) and 92067 (Rancho Santa Fe) ZIP codes. Lately, however, some newcomers have entered the hallowed price range: Chula Vista, Carlsbad, Poway and Downtown San Diego.

Those who persist in thinking that the sky is falling will be heartened to learn that prices in the $1 million-plus category continue to rise. Those who dwell on the median price of housing (as this is the number usually reported), should consider that a far more accurate reading of the market can be obtained by looking at prices per square foot. In the luxury market, prices per square foot continue to rise — perhaps not as rapidly as in the 2003-2005 period, but rising nonetheless.

Downtown San Diego is leading the way in upscale pricing. Last year, 100 condominiums were sold in 92101 for more than $1 million. In the first six months of 2006, the average price of a $1 million-plus unit sold for $1,598,380 or $845 per square foot, up 14.5 percent from the first six months of 2005. This Downtown prosperity is unusually bold because, in reality, the inventory of units worthy of $1 million-plus is rather slim.

Following Downtown is Rancho Santa Fe with average prices per square foot up 7.6 percent in the first six months of this year. Average price there: a crowd-pleasing $2,875,221, or $590 a square foot. That gets buyers a 4,872-square-foot home on a generous lot. It also comes with an outrageous property tax bill, but for those who can afford $3 million, the tax is a drop in the bucket, easily matched by the water bill and the cost of gardeners. (Recall which ZIP code stood out during the drought a few years back when the local papers published the water usage of the county’s top 25 homeowners.)

La Jolla, forever the laggard to Rancho Santa Fe in the contest for most expensive housing, had an average price of only $2,189,422 in the first six months of 2006 at $787 per square foot, up 2.5 percent over the past year. (The size of the average home sold in La Jolla is significantly smaller than a Rancho Santa Fe home and sited on far smaller lots.)

Overall, the county fared rather well in the $1 million-plus category, with prices averaging $509 per square foot, up 4.8 percent the first half of this year over the same period in 2005.

The strength of the $1 million-plus market can be assessed in two ways. The first is days on market; the second, the ratio between sale price and asking price.

The stability of the sale price to asking price tells you whether sellers are approaching reality in their asking prices. The typical ratio is in the 93 percent-94 percent range and stable over the past year. So sellers are relatively realistic. Of course, those homes that don’t sell probably have unrealistic asking prices.

In terms of days on market, the $1 million-plus range is rather stable. For instance, La Jolla tends to be in the 70-80 day range and Rancho Santa Fe 110 to 120 days. This compares to an overall average of about 60 days in the sub-$1 million range.

On the subdivision scene, it is notable that more than 750 subdivision tract homes were sold for more than $1 million. In 2000, 1 percent of the subdivision homes sold hit this mark, compared to 23 percent in the first half of 2006. This year is on track to match the 2005 total, even though the total homes sold have declined.

In Downtown San Diego, the most vibrant part of the market is the most expensive units. If there is one problem with the Downtown condo market, it is the rather poor selection of luxury units. Hopefully, in the years ahead, the supply of units actually worth more than $1 million expands.

On balance, the rich always have money, and they get richer by buying luxury homes in good times or bad, and just holding on to them, sometimes indefinitely. Today’s market is not geared to the “flipper.” It is aimed directly at those who appreciate and want to live in better quality housing. And after all, San Diego County isn’t such a bad place to live out your life in luxury.

Alan N. Nevin is director of economic research with MarketPointe Realty Advisors (marketpointe.com), a consultancy providing real estate and demographic statistics, feasibility studies and litigation support to the California land use industry and legal professions. Nevin can be reached by e-mail at anevin@sandiegometro.com.