Ask yourself this, do you think it is going to continue down and if so and you don't want to sell because you don't want to take a loss then I ask you do some math. While you hold then your money is locked up, not doing anything for you and in fact possibly losing money if it continues to drop. Now say you sell now and eat that loss and then turn 3% a day on average or what ever % you think you could average per day or per week. How long would it take you to make up that money and are you willing to ride this one to the lower bollinger band now that it has broke below the 20 DMA? If the stock continues down then one day it should rise back up again and you should be fine, the unknown is when it will rise again. If the DOW heads for 7,800 then I suspect it could take it 2 - 4 weeks to get there, MPG would likely struggle during that entire time. Do the math for that period and see if you would be better off selling and making money elsewhere or holding for when the stock returns to the level you purchased. Just giving you some things to think about to help you with your decision. It always comes down to risk / reward factor.
Brad