27 CFR § 70.243 - Exempt amount.
(a) If the payroll period is weekly, an amount equal to:
(1) The sum of:
(i) The standard deduction, and
(b) If the payroll period is not weekly, the amount exempt from levy shall be an amount which as nearly as possible will result in the same total exemption from levy for such individual over a period of time as such individual would have under paragraph (a) of this section if (during such period of time) the individual were paid or received such wages, salary or other income on a regular weekly basis.
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