for ease of use we will discuss this in US dollars
here's a currency converter...
http://www.xe.com/ucc/
and the measure shall be in litres (as 90% of the world is metric now - unlike some luddite countries that refuse to change)
1 litre = 0.26 US gallons or 0.22 UK gallons (see what I mean about luddites - can't even decide which amount it is..?)
For the record - Australia's is about $Aus1.20 = 98.5c US
it's risen by almost 40c/L in the past year....
