I should have specified taxable income. Here’s the gory details:
1.If we have previous year’s taxable incomes for the spouses (sum of the two is not 0), we use those to determine the proportion, so that deals will all the income splitting/sharing.
2.If that doesn't work we use the current total incomes of each spouse. That’s before the CPP/taxes calculations, so no pension splitting/sharing is considered in that case.
3.If that doesn’t work we use the net worths of each spouse (previous year, sum of the two is not 0).
4.If that doesn’t work we use 50%.
This is re-calculated for every year in the TIME MACHINE.
#1 usually works although #2 is often applied in the current year if a user doesn’t bother to enter last year’s taxable incomes in the TM preflight input screens.
#3 and #4 rarely happen.