 video will improve continuously. Therefore it is not a very daring assumption that mobile devices will become competitive as one content channel among others, such as books, newspapers, TV and movies, illustrating a true convergence with the media industry ('mobile media'). Regarding content, the futuristic generation has proven to be large consumers of porno- graphic content on the Internet. Many mobile actors are therefore investigating the area of providing erotic content or indeed pornography as a means to increase ARPU with the increased bandwidth of the 3G systems as an enabler. The availability will be restricted by means of codes for interested paying adults. The possible erotic-pornographic services will be of pull type, not push. Telecom Business A common unit when looking at growth rates is to use the compound annual growth rate (CAGR): the year over year growth rate of an investment etc. over a specified period of time. CAGR is calculated by taking the nth root of the total percentage growth rate where n is the number of years in the period being considered. This can be written as: (Current value/Base value) (1/number of years) CAGR doesn't represent reality. It's an imaginary number that describes the rate at which an investment grew as though it had grown at a steady rate. Figure 4.37 shows an example of use of CAGR. This figure is a forecast of the UK market growth 1998-2010 (Arthur D. Little). Mobile voice £5-11 billion CAGR = % Fixed voice £7.5-8.5 billion CAGR = % Fixed data £7.6-16.5 billion CAGR = % Mobile data £0.2-6 billion CAGR =33% For comparison with the real development, mobile data represented 16 % of the revenue for the mobile operator Vodafone for the last quarter of 2002. The SMS service represents most of the data income. One mobile phone per household develops to individual phones per household. The IP technology for voice services develops with IP PBX, VoIP, IP Centrex and a fast growth in IP-VPN. Messaging is a forecast favourite, both e-mail, SMS and MMS. Another example of pot