On January 1, 2018, Derek Co.'s defined benefit pension plan has an unamortized prior service cost - $124,519. The unamortized prior service cost is being amortized over the expected remaining service lives of covered employees, which consists of a total of 10 employees: . 4 employees are each expected to have 6 years remaining 3 employees are each expected to have 4 years remaining 3 employees are each expected to have 2 years remaining How much amortization of prior service cost will be included in Derek Co.'s pension expense for 2018