Nebraska Revised Statute 14-501.01
A city of the metropolitan class may adopt biennial budgets for biennial periods if such budgets are provided for by a city charter provision. For purposes of this section:
(1) Biennial budget means a budget that provides for a biennial period to determine and carry on the city's financial and taxing affairs; and
(2) Biennial period means the two fiscal years comprising a biennium commencing in odd-numbered or even-numbered years.