The printed form on which returns are to be made under oath to the commission, as required by RCW 15.44.110, shall be known as "monthly assessment report," shall be prepared, signed, and submitted to the commission by each dealer, shipper, handler, producer handler, processor, manufacturer, and distributor not later than the 20th day of the succeeding month for the previous month's volume of milk handled, and shall contain the following information:

(1) Name and address of dealer, shipper, handler, producer handler, processor, manufacturer or distributor.

(2) Assessment rate applicable to fluid milk as provided in WAC 16-145-025. Total amount of producer milk purchased, handled or distributed.

(3) Period for which report is submitted.

(4) Total amount of assessment collected and forwarded to the commission.

(5) Certification by dealer, handler, producer handler, distributor or other person preparing the form.