Sorry about your personal loss. The settlement is tax free to you because it is compensation for personal physical injury. However, if any part of the settlement is for punitive damages, those are taxable.
A statutory method of depreciation allowing accelerated rates for most types of property used in business and income-producing activities during the years 1981 through 1986. It has been superseded by the modified accelerated cost recovery system (MACRS) for assets placed in service after 1986.