Worldwide mobile phone market is expected to grow only 1.4 percent year over year in 2012, the lowest annual growth rate in three years, research firm International Data Corp. (IDC) predicted in a report on Tuesday. The slower pace of growth in mobile phone sales is due to the weak global economy, IDC analysts noted. \"Sluggish economic conditions worldwide have cast a pall over the mobile phone market this year,\" Kevin Restivo, a senior research analyst at IDC, said in a statement. Despite the slowing growth of the overall mobile phone market, demand for smartphone continues to be robust as IDC projected that global smartphone shipments in 2012 will increase 45.1 percent year over year to 717.5 million units. With smartphones included, vendors worldwide are expected to ship a total of more than 1.7 billion units of mobile phones this year, according to the IDC report. Strong smartphone growth can be attributed to a variety of factors including steep device subsidies from carriers in mature markets, as well as more options of lower-cost handsets in emerging markets such as China, IDC analysts said.