An employer is not prohibited from prospectively reducing the predetermined salary amount to be paid regularly to a white-collar (Part 541) exempt employee during a business or economic slowdown, provided the change is bona fide and not used as a device to evade the salary basis requirements. Such a predetermined regular salary reduction, not related to the quantity or quality of work performed, will not result in loss of the exemption, as long as the employee still receives on a salary basis at least $455 per week. On the other hand, deductions from predetermined pay occasioned by day-to-day or week-to-week determinations of the operating requirements of the business constitute impermissible deductions from the predetermined salary and would result in loss of the exemption. The difference is that the first instance involves a prospective reduction in the predetermined pay to reflect the long term business needs, rather than a short-term, day-to-day or week-to-week deduction from the fixed salary for absences from scheduled work occasioned by the employer or its business operations.

Source: US Department of Labor, Wage and Hour Division: Frequently Asked Questions Regarding Furloughs and Other Reductions in Pay and Hours Worked Issues, July 2009.