It is the intent that the accident fund shall ultimately become neither more nor less than self-supporting, except as provided in RCW 51.16.105 and, if in the adjustment of premium rates by the director the moneys paid into the fund by any class or classes shall be insufficient to properly and safely distribute the burden of accidents occurring therein, the department may divide, rearrange, or consolidate such class or classes, making such adjustment or transfer of funds as it may deem proper. The director shall make corrections of classifications or subclassifications or changes in rates, classes and subclasses when the best interest of such classes or subclasses will be served thereby.