180 but don't forget the Medicare levy plus various flood/natural disaster levies that the feds kick in every now and then. It's close enough to 50% to feel like "half"...
It's a shame the reality is very different (allowing 45% + 3% in levies):
[TABLE="width: 500"]
[TR]
[TD]Pay[/TD]
[TD]nominal Tax[/TD]
[TD]Percentage[/TD]
[/TR]
[TR]
[TD="align: right"]200,000[/TD]
[TD="align: right"]64147[/TD]
[TD="align: right"]32[/TD]
[/TR]
[TR]
[TD="align: right"]300,000[/TD]
[TD="align: right"]112147[/TD]
[TD="align: right"]37.3[/TD]
[/TR]
[TR]
[TD="align: right"]500,000[/TD]
[TD="align: right"]208147[/TD]
[TD="align: right"]41.6[/TD]
[/TR]
[TR]
[TD="align: right"]1,000,000[/TD]
[TD="align: right"]448147[/TD]
[TD="align: right"]44.8[/TD]
[/TR]
[TR]
[TD="align: right"]10,000,000[/TD]
[TD="align: right"]4768147[/TD]
[TD="align: right"]47.7[/TD]
[/TR]
[TR]
[TD="align: right"]100,000,000[/TD]
[TD="align: right"]47968147[/TD]
[TD="align: right"]47.9[/TD]
[/TR]
[/TABLE]