In France, nearly 99% of the population can be reached by phone. Nevertheless, recent developments in telephony have forced telephone survey designers to revise their selection methods in order to reach the entire population, which consists of different types of households: landline subscribers with the incumbent carrier, exclusive mobile phone users, and households with "full unbundling," that is, those who have switched from the incumbent carrier to new operators. According to the French Regulatory Authority for Electronic Communications and Postal Services (ARCEP), the number of households with full unbundling exceeded 7 million in 2010. Some of these households have the particular characteristic of being reachable only via a number starting with 08 or 09 (2 to 4% of all households in 2010 according to GfK-ISL/Médiamétrie and ARCEP).[excerpt from press release]