When a company sponsors a postretirement benefit plan other than a pension plan, benefits typically are not earned by employees on the basis of a formula, so assigning the service cost to specific periods is more difficult. The FASB Accounting Standards Codification represents the single source of authoritative U.S. generally accepted accounting principles.

Required:
1. Obtain the relevant authoritative literature on how a firm should attribute the expected postretirement benefit obligation to years of service using the FASB's Codification Research System at the FASB website (www.fasb.org). Find the specific citations that describe the guidelines for each of the following questions:
a. What is the objective for attributing expected postretirement benefit obligations to years of service?
b. When does the attribution period for expected postretirement benefits begin for an employee?
c. When does the attribution period for expected postretirement benefits end for an employee?
2. What are the guidelines for each?