Section 9 of the Federal Child Support Guidelines states that:
Where a spouse exercises a right of access to, or has physical custody of, a child for not less than 40 per cent of the time over the course of a year, the amount of the child support order must be determined by taking into account
(a) the amounts set out in the applicable tables for each of the spouses;
(b) the increased costs of shared custody arrangements; and
(c) the conditions, means, needs and other circumstances of each spouse and of any child for whom support is sought.