For taxable years beginning after December 31, 2019, section 1400Z-2 (relating to capital gains invested in opportunity zones) is modified so that an increase in basis is twice the amount determined under section 1400Z-2 (b) (2) (B) (iii) for an investment held in a Wisconsin qualified opportunity fund for at least 5 years or under section 1400Z-2 (b) (2) (B) (iv) for an investment held in a Wisconsin qualified opportunity fund for at least 7 years. In this subdivision, “Wisconsin qualified opportunity fund” has the meaning given in s. 71.05 (25m) (a) 2.

In the form and manner prescribed by the department, a fund shall annually certify to each investor and the department that it qualifies as a Wisconsin qualified opportunity fund for the fund’s taxable year. A fund shall make the annual certifications under this subdivision no later than the due date, including extensions, of the fund’s corresponding income or franchise tax return under this chapter.