I googled Alaska and this is what is on your court web-site
Rule 90.3. Child Support Awards.
(a) Guidelines--Primary Physical Custody. A child support award in a case in which one parent is awarded primary physical custody as defined by paragraph (f) will be calculated as an amount equal to the adjusted annual income of the non-custodial parent multiplied by a percentage specified in subparagraph (a)(2).
(1) Adjusted annual income as used in this rule means the parent's total income from all sources minus:
(A) mandatory deductions such as:
(i) federal, state, and local income tax,
(ii) Social Security tax or the equivalent contribution to an alternate plan established by a public employer, and self-employment tax,
(iii) Medicare tax,
(iv) mandatory union dues,
(v) mandatory contributions to a retirement or pension plan;
(B) voluntary contributions to a retirement or pension plan or account in which the earnings are tax-free or tax-deferred, except that the total amount of these voluntary contributions plus any mandatory contributions under item (a)(1)(A)(v) above may not exceed 7.5% of the parent's gross wages and self-employment income;
(C) child support and alimony payments arising from prior relationships which are required by other court or administrative proceedings and actually paid;
(D) child support for children from prior relationships living with the parent, calculated by using the formula provided by this rule; and
(E) work-related child care expenses for the children who are the subject of the child support order.
(2) The percentage by which the non-custodial parent's adjusted income must be multiplied in order to calculate the child support award is:
(A) 20% (.20) for one child;
(B) 27% (.27) for two children;
(C) 33% (.33) for three children; and
(D) an extra 3% (.03) for each additional child.
(3) The court may allow the obligor parent to reduce child support payments by up to 75% for any period in which the obligor parent has extended visitation of over 27 consecutive days. The order must specify the amount of the reduction which is allowable if the extended visitation is exercised.
(4) Potential Income. The court may calculate child support based on a determination of the potential income of a parent who voluntarily and unreasonably is unemployed or underemployed. A determination of potential income may not be made for a parent who is physically or mentally incapacitated, or who is caring for a child under two years of age to whom the parents owe a joint legal responsibility. Potential income will be based upon the parent's work history, qualifications, and job opportunities. The court also may impute potential income for non-income or low income producing assets.
(b) Shared, Divided, and Hybrid Physical Custody.
(1) Shared Physical Custody. A child support award in a case in which the parents are awarded shared physical custody as defined by paragraph (f) will be calculated by:
(A) Calculating the annual amount each parent would pay to the other parent under paragraph (a) assuming the other parent had primary custody. In this calculation the income limit in subparagraph (c)(2) and the minimum support amount in subparagraph (c)(3) apply.
(B) Multiplying this amount for each parent by the percentage of time the other parent will have physical custody of the children. However, if the court finds that the percentage of time each parent will have physical custody will not accurately reflect the ratio of funds each parent will directly spend on supporting the children, the court shall vary this percentage to reflect its findings.
(C) The parent with the larger figure calculated in the preceding subparagraph is the obligor parent and the annual award is equal to the difference between the two figures multiplied by 1.5. However, if this figure is higher than the amount of support which would be calculated under paragraph (a) assuming primary custody, the annual support is the amount calculated under paragraph (a).