Partnership interests.

Whenever a person other than a corporation sells, exchanges or otherwise disposes of an ownership interest in a partnership in a transaction in which gain or loss is recognized, an appropriate modification to federal adjusted gross income may be made in the year of disposition to reflect an increase or decrease in the basis of the partnership interest equal to any reductions or additions in such basis occurring in calendar or fiscal years prior to 1975 as a result of losses or gains relating to business or property which had a situs outside of this state under the provisions of s. 71.07, 1985 stats., in effect for years prior to 1975.