Nearly one-third of the world's 6.5 billion people have a mobile phone, according to industry statistics that show the number of mobile phone customers passed the 2 billion mark over the weekend.
However, as the industry celebrated another milestone, evidence emerged to show that the market's growth, as measured by net new additional customers, is likely to peak this year and fall rapidly over the rest of the decade.
While a record additional 380 million subscriptions are forecast for 2005 - comfortably exceeding the 335 million for last year - growth is expected to start slowing sharply from 2006. The chart from Informa Telecoms and Media shows that by 2010, net additional subscriptions will be down to 100 million.
Devine Kofiloto, the principal analyst at Informa, said: "The continued growth in overall net additions cannot be sustained over the next couple of years despite the phenomenal strong growth coming from many of the key developing markets such as China, Russia, Indonesia and India. As growth in developed markets slows down and developing markets begin moving towards maturity, the net effect will see overall growth trending downwards from 2005."
Martin Garner, at Ovum, said: "There are several cases, such as Sweden, Italy and the UK, where market penetration is over 100 per cent of the population. Here, most of the interest is about people trading up to new phones and network services."