I've done the calculations for Snork Maiden's tax return for this tax year. The tax year runs from 1st July to 30th June in Australia. The figures ignore employer and employee contributions to superannuation (retirement account) which amount to a lot of extra income. Everything is in Australian Dollars of course.
Looks like she needs to pay extra tax :( Compared to last year the Medicare Levy has increased by 0.5%, which means an extra $450 of tax before anything else So, despite income being up only by 3% taxes are up by 5%. Salary is unchanged because the current Enterprise Agreement has expired and the union hasn't agreed a new deal with the employer. Investment income is up as are tax credits derived from investment income (by more than 50% in the latter case). Deductions are steeply down because there was no unreimbursed work related travel this year. Gifts and donations are up 1100%. Snork Maiden started donating $40 per month to Save the Children a month before the end of the last tax year.
The average tax rate on taxable income is 24.94%. Gross income before deductions and tax credits is not a lot higher than taxable income and so the tax rate on "gross cash income" is only slightly lower. The difference will be much bigger on my own income.
Here are the reports on Snork Maiden's taxes for all previous years: