What is the test for imputing "declared income" on a motion to change the amount of support for the wife?

The wife relies on the decision of Pazaratz J. in Trang v. Trang (2013) 2013 ONSC 1980 (CanLII), 29 R.F.L. (7th) 364 (Ont. S.C.J.) for the proposition that a moving party has the burden of demonstrating why changed circumstances make it no longer necessary to impute income. The rationale for this approach was explained by Pazaratz J.: 53. If “declared income” automatically prevailed on a motion to change support, it would defeat the purpose of imputing income in the first place. It might even be a disincentive for payors to participate in the initial court process. They could wait to see if the court imputes income, and how much. If dissatisfied with the amount, the payor could later return to court waving their tax returns, to suggest that the original judge got it wrong. 54. Support claimants should not be forced to go through this two-step process. Our family court system certainly can’t afford it. 55. Similarly, the onus should not fall on the support recipient to establish why income should still be imputed on a motion to change. That determination has already been made. The onus is on the support payor to establish that there should be a change in the way their income is to be calculated.