A gains-and-loss analysis for the week of Oct 4 to 11 unearthed interesting deals. A 2,508 sq ft unit at Chelsea Gardens in prime District 10 was sold at a loss of $810,200, despite being held for more than 19 years. The unit was purchased from the developer in August 1997 for $1,838 psf and resold for $1,515 psf this month. The loss margin works out to 18%, or 1% annually.