According to Infonetics Research, the worldwide telecom carrier capex grew by 7% in 2007 to $251bn, driven by mobile and broadband demand. The research firm forecasts that worldwide capex will plateau in 2009 and begin declining in 2010. In developed countries, the investment cycle in mobile (mainly 3G) is on the end drawing capex down, but in developing countries the investment cycle is still there and up. As a result, capex-to-revenue rate is between 15% and 16% in developed countries versus extra 25% in developing countries. 50% of worldwide capex is made with the world' s top 15 SPs.