Neb. Rev. Stat. § 18-2804

Each governing body may establish a separate fiscal year for each proprietary function, except that any proprietary function which is subsidized by appropriations from the municipality's general fund shall have the same fiscal year as the municipality. For purposes of this section, subsidization shall mean that the costs of operation of a proprietary function are regularly financed by appropriations from the municipality's general fund in excess of the amount paid by the municipality to the proprietary function for actual service or services received.