The local government investment pool (LGIP) daily yield, as calculated by the state treasurer, is the proper interest rate to be used as the annual rate of interest for the purpose of calculating a lump sum payment to irrigation districts for lands acquired by the Washington state department of transportation per RCW 87.03.810. The last published daily yield prior to the official transfer of property should be used for the calculation. The last published daily yield means the day prior to the day that the deed is recorded.
Wash. Admin. Code § 284-74-700