Say that Australia has a working population of 11,565,470 people, and that the average salary is $26,450 annually. How much tax revenue would Australia generate each year by instituting a 31.4% income tax?

Calculating the amount taxed from each person in the working population:

31.4% * 26450 = $8305.30 per person

The amount of tax collected from the whole population:

8305.30 * 11565470 = $96,054,697,990 ⇒ This is the annual tax revenue