Estimated full year amortization expense relating to intangible assets for each of the next five years ending December 31 is as follows: | 
 |  |  |  |  | 
(in millions)  |    |    | 
2014  |    | $  | 500  | 
 
  | 
2015  |    | 478  | 
 
  | 
2016  |    | 449  | 
 
  | 
2017  |    | 411  | 
 
  | 
2018  |    | 332  | 
 
  | 
  
    
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