How is retroactive child support calculated when the payor's income is based on the previous year's income?

Ontario, Canada

The following excerpt is from Taylor v. Schultz, 2020 ONSC 5974 (CanLII):

During submissions, counsel for the mother submitted that retroactive child support should be based on the previous year’s income. I do not agree. Where the amount of child support that should have been paid in a prior year is under consideration, the payor’s actual income for that year is the amount that should be used to calculate support for that year. The most current information must be used: Vanos v. Vanos, 2010 ONCA 876.

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