on top of the above a GST of 9.18.
So the tax is 18.18 + 9.18 = 27.36 - about 1/3 of the total price, expensive tax, but still cheaper than your flight to NZ.
Luckily the flight between Christchurch and Sydney (and Sydney to Auckland) is part of the award ticket itinerary so I only need to buy the Australia domestic flights.
For the whole ticket from Florida to New Zealand to Australia and back, I paid USD94.5 tax. I was surprised by that little - heck the trip to San Francisco has $40.50 tax on a $99 ticket!(It was a big sale on that route, usually would be $250+)