For the purposes of this subsection, "net investment return" means the rate of investment return that is in an amount that does not exceed the actual expense not offset by other deductions and that is credited to the variable annuity contract according to the terms of the contract after deductions for tax charges, if any, for asset charges either at a rate that does not exceed the rate stated in the contract, or if the contract is issued by a nonprofit corporation under which the contract holder participates fully in the investment, for mortality and expense experience of the account.
A.R.S. § 20-2636