After due consideration of the record, the Secretary shall render a decision. Such decision shall become a part of the record and shall include:
(a) A statement of findings and conclusions, including the reasons or basis for such findings, upon all the material issues of fact or law presented on the record.
(b) A ruling upon proposed findings and proposed conclusions not previously ruled upon in the record.
(c) A ruling upon exceptions filed by interested persons.
(d) Either a denial of the proposal to issue a rule, or, if the findings upon the record so warrant, a rule, the provisions of which shall be set forth and such rule shall be complete.