Rush, J.
Irregular income—bonuses, commissions, and the like—can make applying the Child Support Rules and Guidelines challenging. Practitioners and courts have worked to craft suitable solutions, and we certainly encourage parents to negotiate creative agreements that accurately account for irregular income, avoid litigation, and adequately provide for children. Here, in an effort to craft a workable solution, Mother and Father made a seemingly simple agreement: to recalculate their support obligation annually using the Guidelines.
But despite their best-laid plans, their agreement went awry. Its terms are silent about which version of the Guidelines applies. As required by law, this Court has reviewed and amended the Guidelines four times in the last 24 years—most recently in 2010, the year after Mother and Father’s agreement was finalized. And the 2010 changes significantly increased support obligations for high-income parents like Father.
We therefore face a question of contract interpretation: Does the Agreement incorporate the version of the Guidelines in effect at the time the Agreement was made, or the one in effect for each particular year’s income? The trial court interpreted the Agreement as incorporating the version that applied to a particular year’s income, and we agree. Since the Guidelines are regularly amended to fit changing economic conditions, we hold that this Agreement anticipates and incorporates those future changes, because it does not specify otherwise.
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Conclusion
We read the Distribution Clause as requiring Father to calculate each year’s child-support obligation by applying the version of the Guidelines applicable to that year’s income. The language and structure of the Distribution Clause, the regularly changing nature of the Guidelines, and the basic purpose of those periodic changes and of child support generally, all lead us to that conclusion. We therefore affirm the trial court.
Dickson, C.J. and Rucker, David, and Massa, JJ., concur.