According to the Chron, the real-estate pricing firm Zillow.com reports that twenty percent of all Bay Area homes are “underwater,” or worth less than their mortgages. As any obsessive homeowner will tell you, Zillow has not exactly been the most reliable calculator of such figures, but let’s look at ’em anyway. In Berkeley, the southwestern areas are the hardest-hit, with a little over eleven percent of homes underwater, and a little under a third of homes recently sold at a loss. In Oakland, the Elmhurst District is the big loser; at least percent of homes are underwater, and more than 68 percent of recent home sales couldn’t match the mortgage price. Concord has been hit all over; not a single zip code has less than a 28 percent underwater rate. And woe betide you Pittsburg and Antioch residents, where almost half the homes are underwater. Hope you guys have some life savers handy.