The contributions collected become part of a trust fund from which all Part A payments
are made. This fund is administered by a Board of Trustees consisting of the Secretary
of the Treasury (who is the Managing Trustee), the Secretary of Labor, and the Secretary
of Health and Human Services all ex-officio. The Managing Trustee is authorized to
invest trust funds only in interest-bearing obligations of the United States, or in
obligations guaranteed as to both principal and interest by the United States not
need for current withdrawals, and to make payments from the fund for purposes of Part
A, including administrative expenses.