Definitions.

“Farmers or fishers” are individuals, estates or trusts whose estimated gross income from farming or fishing for the taxable year is at least two-thirds of the total estimated gross income from all sources for the taxable year or individuals, estates or trusts whose gross income from farming or fishing for the preceding taxable year was at least two-thirds of the total gross income from all sources shown on that return. If a person files a joint return, the income of both that person and that person’s spouse shall be considered in determining whether the person is a farmer or fisher.

“Return” means a return that would show the tax properly due.

“Tax shown on the return” and “tax for the taxable year” mean the net tax imposed under s. 71.02 after reduction for exemptions to, and credits against, that tax but before reduction by amounts withheld under subch. X and before reduction for amounts paid as estimated tax under this section for that tax plus the surcharge imposed under s. 77.93 before reduction for amounts paid as estimated tax under this section for that surcharge.