Lucy

Starting super balance: $3.7 million
Ending super balance: $4.1 million

Accounting for some personal financial decisions throughout the year, Lucy's adjusted total super balance at the end of the year is $4.05 million.

That means her superannuation earnings for the year are $350,000.

But only about one quarter - or 26.8 per cent - of those earnings are taxed because only one quarter of her adjusted super balance is above the $3 million threshold.

That puts her taxable earnings at: $93,905.

Since 15 per cent of $93,905 is $14,086, that is the additional tax bill Lucy will have to pay at the end of the year.