Apportionment; other methods.

If the apportionment methods of ss. 220.15 and 220.151 do not fairly represent the extent of a taxpayer’s tax base attributable to this state, the taxpayer may petition for, or the department may require, in respect to all or any part of the taxpayer’s tax base, if reasonable:

(1) Separate accounting;

(2) The exclusion of any one or more factors;

(3) The inclusion of one or more additional factors which will fairly represent the taxpayer’s tax base attributable to this state; or

(4) The employment of any other method which will produce an equitable apportionment.