Wis. Admin. Code § Tax 2.41
(1) When the separate accounting method is used, separate records must be kept of sales, cost of sales and expenses for the Wisconsin business as distinct from the remainder of the business. Overhead items of income and expense must then be allocated to the business within and without Wisconsin upon a basis or combination of bases justified by the facts and conditions. For example: the ratio of Wisconsin sales to total sales usually represents a satisfactory basis for a merchandising business, while the ratio of direct cost of material and labor in Wisconsin to the total gives a more accurate result for a construction business.
(2) Net rentals received from real estate held purely for investment purposes and not used in the operation of the business are not subject to allocation but are taxable in full if the property is located in Wisconsin. Gross rentals must be reduced by all expenses related to such investment property.
Note: Section Tax 2.41 interprets ss. 71.04 (4) and 71.25 (6), Stats.
History: 1-2-56; am. Register, February, 1958, No. 26, eff. 3-1-58; am. Register, November, 1977, No. 263, eff. 12-1-77.