Payroll Taxes

History of Changes to the PayrollTax Module

The PayrollTax module is written entirely in the "forms" language. Forms, like TRIM3 program rules, are stored in the TRIM3 database and can be modified by the user. Therefore, the PayrollTax module’s capabilities depend on the version of "forms" included in the run. The PayrollTax documentation describes the capabilities of the "forms" used in the revised version of the 2003 PayrollTax baseline simulation (PT2003_v2). Changes introduced beginning with the version of forms used in PT2003_v2 are listed below.

Changes Effective with the Forms Used in PT2003_V2

• Civil Service Retirement System (CSRS) workers are randomly selected from federal employees who were 21 or older in 1983 (federal employees hired after 1983 are covered by Old Age, Survivors, and Disability Insurance (OASDI) rather than CSRS). Previously, CSRS workers were randomly selected from all federal employees, without regard to age.
• Program rule FedEmpPostalRate was created in order to allow users to specify a separate rate for the CSRS employer contribution for postal workers. Previously, the CSRS employer contribution rate for postal workers was obtained from FedEmployerRate.
• Medicare Hospital Insurance Fund (HI) taxes are simulated for state and local employees who are exempt from OASDI and who were under age 21 in 1985 (HI coverage was made mandatory for newly hired state and local workers beginning March 31, 1986). Previously, HI taxes were not simulated for state and local employees who are simulated as exempt from OASDI.
• Summary tables B2 and B3 were created.