Neb. Rev. Stat. §§ 14-2138
The metropolitan utilities district shall pay to the city of the metropolitan class a sum equivalent to two percent of the annual gross revenue derived from all retail sales of water and gas sold by such district within such city, except that retail sales of gas shall not include the retail sale of natural gas used as vehicular fuel. Such sum shall be paid on a quarterly basis, the last quarterly payment to be made not later than the thirtieth day of January of the next succeeding year, except that annual payments to such city shall not be less than five hundred thousand dollars. Such city shall not levy or collect any license, occupation, or excise tax upon or from such district. All payments provided by this section shall be allocated by the district among the several utilities operated by it upon such basis as the district shall determine.
Neb. Rev. Stat. §§ 14-2138