350.42.8. A registrant shall, in determining the net tax of the registrant for a reporting period that includes a particular time, add the amount determined by the formula in the second paragraph if(1) the registrant makes a supply of a beverage in a returnable container of a particular class in respect of which the registrant is a specified beverage retailer;
(2) the first and second paragraphs of section 350.42.4 apply in determining the value of the consideration for the supply; and
(3) the registrant makes at the particular time a supply of the returnable container used and empty for consideration without having acquired it used and empty for consideration.
For the purposes of the formula,(1) A is the rate of tax specified in the first paragraph of section 16; and
(2) B is the refund for a returnable container of that class.