3G iPhone costs 10 percent of average after-tax income in NZ

New Zealand iPhone addicts might find their habit expensive to feed.

Vodafone New Zealand announced iPhone prices this morning. Monthly plans start at NZ$80 for 250MB of data, not too bad, but the 1GB plan is a hefty NZ$250. To put this figure in perspective it is around 10 percent of the average after tax income.

Here is the calculation:

1. The most recent survey published by Statistics New Zealand says the average weekly income from all sources for the 2007 June quarter was $667.
2. That’s $34, 684 a year.
3. According to the IRD’s online tax calculator, the annual tax bill for this salary would be $6763.
4. Which means the average New Zealand after tax income is $27,921.
5. Vodafone New Zealand’s minimum iPhone plan costs 12 * $250 or $3,000
6. Which is slightly more than 10 percent of the average after tax income.

Just how much data will the typical 3G iPhone user need?

There’s this from Germany (reported on ZDnet):

René Obermann, CEO of Deutsche Telekom AG, says iPhone is driving up average wireless data usage as much as 30 times higher than on other phones. The average Internet usage for an iPhone customer is more than 100 MBytes. Which is 30 times the use for their average contract-based consumer.

Britain’s The Financial Times reports:

Mr Key is excited about how iPhone customers are turning out to have a big appetite for data services. About 60 percent are sending or receiving more than 25MB of data a month, which is the equivalent of sending 7,500 e-mails.

In the US, Fortune magazine says:

We have been told that iPhone users are consuming “well over” 100 MB per month (compared to Blackberry around 10 MB).

It seems that 1Gb is a lot more data than most existing iPhone users need in 2008, but 3G downloads data faster so demand is likely to be significantly higher. Even so, if these quotes concerning overseas usage are accurate, Vodafone’s 250MB plan will be more than adequate for everyday users and only hard core users will tithe themselves.