Wis. Stat. § 562.052: Employees at racetrack.

At least 85 percent of the individuals employed by a licensee under s. 562.05 (1) (a) to (c), or by a person providing services under a contract with such a licensee, who work at the racetrack where races are held pursuant to the license shall have been residents of this state for at least one year immediately before their employment at the racetrack.