(1) Obligations of the United States, including those of its agencies and instrumentalities;
(2) Obligations of public housing agencies issued pursuant to the United States Housing Act of 1937, as amended;
(3) Obligations of the State of Oregon or any county, city, school district, port district or other public body with the power to levy taxes issued pursuant to the Constitution or statutes of the State of Oregon or the charter or ordinances of any county or city within the State of Oregon, if the issuing body has not been in default with respect to the payment of principal or interest on any of its obligations within five years preceding the date of the investment; or
(4) Shares in any mutual fund or unit trust, the assets of which are invested solely in obligations of the type described in subsections (1) to (3) of this section. [1997 c.631 §154]