"With each generation of mobile evolution, such as 3G, 4G and now 5G, the cost of upgrading goes up. In telecommunication, returns are all about scale - as the fixed costs of the network are about the same for everyone," Chris Lane, an analyst at Sanford C. Bernstein, said in a telephone interview. "As you slip down the ranks, you become more and more sub-scale and profitability keeps diminishing." Possible combinations: 1. Vodafone/Idea Vodafone Group Plc's India unit and Idea have been in talks to consolidate, according to people familiar with the matter, who asked not to be identified as the talks are private. The talks were first reported by CNBC-TV18 in August. A merger would create a carrier with 387 million subscribers, a 36 percent market share and pan-India 4G spectrum. A deal would also give Vodafone a listing in India, which it has been considering since at least 2011. At reported debt levels, the merged entity would have net debt of 718 billion rupees.