In any instance where an irrigation district having outstanding refunding bonds issued under the provision of this chapter, sells or rents a tract of land previously acquired by sale on account of delinquent district assessments, the proceeds of said sale or lease shall be distributed to the expense fund and the refunding bond fund of the district in proportion to the respective amounts of the district exactions made against said tract of land for the benefit of these two funds payable in the year in which the district assessment for which said tract was sold, became delinquent.