There are some stories going around about the iPhone sales numbers, apparently started by an Inquirer piece based on bad maths. Ars technica has done a good piece analysing various figures, and concludes that the first million iPhones were sold at an average rate of 13,514 iPhones per day, while in the fourth quarter of 2007 the average sale rate was 24,163 iPhones sold per day, and early January saw average sales of 21,142 per day. There’s a couple of things to note here: First, any seasonal dip in iPhone sales from Q4 to Q1 was likely exacerbated by the faithful waiting until MacWorld was over before making any new Apple (NSDQ: AAPL) purchase. Second, the iPhone was launched in France, the UK and Germany in Q4 so sales should have gone up, but don’t make the mistake of thinking they should have quadrupled—The three European countries combined have about 207 million people, compared to the US population of 301 million. I think sale figures will be sustained mostly by opening new markets, and when that falls off new models of the phones will be introduced.

• Another Report on iPhone’s UK Sales: Slightly Short of Projections
• Jobs’ Macworld Keynote: Minor iPhone Updates, Four Million Sold