How can exchange rates change to reduce the wage differential between countries​

Interpreting the income tax expense footnote the income tax footnote to the financial statements of fedex corporation follows. the components of the provision for income taxes for the years ended may 31 were as follows: ($ millions) 2010 2009 2008 current provision domestic federal $ 36 $ (35) $ 514 state and local 54 18 74 foreign 207 214 242 297 197 830 deferred provisions (benefit) domestic federal 408 327 31 state and local 15 48 (2) foreign (10) 7 32 413 382 61 provision for income taxes $ 710 $ 579 $ 891 (a)what is the amount of income tax expense reported in fedex's 2010, 2009, and 2008 income statements?