[["millions of dollars", "2007", "2006", "2005"], ["cash provided by operating activities", "$ 3277", "$ 2880", "$ 2595"], ["cash used in investing activities", "-2426 ( 2426 )", "-2042 ( 2042 )", "-2047 ( 2047 )"], ["dividends paid", "-364 ( 364 )", "-322 ( 322 )", "-314 ( 314 )"], ["free cash flow", "$ 487", "$ 516", "$ 234"]]