OAR 150-314-0339
Proration of Deductions
(1)
This rule adopts a model regulation recommended by the Multistate Tax Commission to promote uniform treatment of this item by the states.(2)
Proration of deductions. In most cases an allowable deduction of a taxpayer will be applicable only to the apportionable income arising from a particular trade or business or to a particular item of nonapportionable income. In some cases an allowable deduction may be applicable to the apportionable incomes of more than one trade or business or to several items of nonapportionable income. In such cases the deduction must be prorated among such trades or businesses and such items of nonapportionable income in a manner that fairly distributes the deduction among the classes of income to which it is applicable.(3)
Year to year consistency. In filing returns with this state, if the taxpayer departs from or modifies the manner of prorating any such deduction used in returns for prior years, the taxpayer must disclose in the return for the current year the nature and extent of the modification.
Source:
Rule 150-314-0339 — Proration of Deductions, https://secure.sos.state.or.us/oard/view.action?ruleNumber=150-314-0339
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