I understand your confusion. Like Damion said our area hasn't seen drops like that in the value of homes in such a short time period. I thought of only one other thing that may have caused this problem. In that time period we saw a lot of foreclosures hit the market. It is possible that in October your area didn't have many of these foreclosed properties. By February there were a lot more foreclosures on the market and possibly more in your area. The banks were so overwhelmed with foreclosed properties that they were pricing them low to move them. The influx of foreclosures, although higher than normal, isn't as bad now unfortunately though your appraisal will still show them as comparable sold homes and this may continue to effect the value of your home.
Let me give you an example. If you have two identical homes, all things being equal, and one is a conventional sale and the other is a short sale and one is priced at $200,000 and the other is $150,000, which one are you going to purchase?
My sympathies go out to you if, in fact, these are accurate appraisals and you are a victim of the economic factors in your area. Check with your local RealtorÂ® and ask them to do a market analysis for you to see what is going on in your neighborhood. If the CMA produces a big discrepancy, it might be worthwhile to talk with the appraiser or get a new appraisal.