. the fair value is estimated based primarily upon future cash flows ( discounted at the company 2019s credit adjusted risk-free rate ) or other reasonable estimates of fair market value . assets to be disposed of are adjusted to the fair value less the cost to sell if less than the book value . the company recorded impairment charges included in sg&a expense of approximately $ 0.2 million in the 2007 predecessor period , $ 9.4 million in 2006 and $ 0