British mobile phone giant Vodafone said on Tuesday that net profits dropped 11 percent to £6.68 billion (7.8 billion euros, $10.7 billion) in the group\'s first half but was confident about the outlook. Profit after tax for the six months to September 30 compared with net earnings of £7.54 billion in the same part of 2010, which included proceeds from the sale of its stake in China Mobile, Vodafone said in a statement. Revenues rose 4.1 percent to £23.52 billion in the reporting period. Chief executive Vittorio Colao was optimistic about the future. \"Although we remain mindful of the uncertain economic outlook, we are confident that we have the right strategy and capabilities to continue to perform consistently through top line growth, cost efficiency, investment and cash generation,\" he said in the statement.