On January 1, 2018, Derek Co.'s defined benefit pension plan has an unamortized prior service cost - $161,000. The unamortized prior service cost is being amortized over the expected remaining service lives of covered employees, which consists of a total of 11 employees: 4 employees are each expected to have 6 years remaining . 4 employees are each expected to have 5 years remaining . 3 employees are each expected to have 2 year remaining How much amortization of prior service cost will be included in Derek Co.'s pension expense for 2018