Haw. Rev. Stat. § 393-46: Income directly attributable to the business.

(a) "Income directly attributable to the business" means gross profits from the business minus deductions for:

(1) Compensation of officers;

(2) Salaries and wages, except wages paid by an individual proprietor to oneself;

(3) Repairs;

(4) Taxes on business and business property;

(5) Business advertising;

(6) Amounts contributed to employee benefit plans;

(7) Interest on business indebtedness;

(8) Rent on business property; and

(9) Other expenses necessary for the current conduct of business.

(b) Deductions shall not include:

(1) Bad debts;

(2) Contributions or gifts, other than those listed under subsection (a)(6);

(3) Amortization and depreciation; or

(4) Losses by fire, storm, casualty, or theft.

(c) The director may promulgate rules and regulations necessary to define income directly attributable to business for the purpose of section 393-45.