It could include reporting for an annuity.
Form RRB-1099-R reports the total gross payments, repayments and the related U.S. Federal income tax withheld from the Non- Social Security Equivalent Benefit (NSSEB) portion of tier I, tier II, vested dual benefit (VDB), and supplemental annuity payments. Form RRB-1099-R is used for U.S. citizens. These payments are treated as private pensions for U.S. Federal income tax purposes. For more information about these payments and Form RRB-1099-R, refer to IRS Publication 575, Pension and Annuity Income.