extrapolating the tasmanian roll out

http://www.heraldsun.com.au/news/national/broadband-big-waste-risk/story-e6frf7l6-1225854983096

"Concern has been growing at the cost of the $43 billion network since Corning Cable Systems was awarded a contract to connect 5000 homes to the NBN in Tasmania at a cost of $38 million or $7600 each."

"The Tasmanian rollout is mainly using overhead cabling. Underground cabling would cost four times as much to deploy in some instances."

Since the Rudd government refuse to provide any insight into their costings for the NBN , lets do our own.

Using the Tasmanian rollout which cost $7600 per residence using the cheaper overhead cabling method (the one that you use when going it alone without Telstra pits and ducts)we see that 22 million australians @ 7600 each gets us to 154 thousand million ie 154 billion.
If they were to use the overhead cabling however the ongoing maintainance becomes unaffordable ( but that would be someone elses problem wouldnt it Kev)
Alternatively they could do the smarter thing and install in the ground (not using telstras ducts) which might on average only boost the price on average 2 times not the 4 times over the cost of overhead cabling. We get to 300 billion for a brand spanking new Rudd certified NBN. Not bad value mr Rudd. Wait... what was that....you have a report that shows figures much less than that? Great lets see it then.