|   |  |  |  |  |  |  |  |  |  |  |  The following table provides the components of our senior unsecured long-term debt:  |     |    |    |    | As of December 31,  |  (MILLIONS OF DOLLARS)  |    | Maturity Date  |    | 2013  | 
 
  |    | 2012  | 
 
  |  6.20%(a)  |    | March 2019  |    | $  | 3,234  | 
 
  |    | $  | 3,327  | 
 
  |  5.35%(a)  |    | March 2015  |    | 3,037  | 
 
  |    | 3,065  | 
 
  |  4.75% euro(b)  |    | June 2016  |    | 2,752  | 
 
  |    | 2,638  | 
 
  |  5.75% euro(b)  |    | June 2021  |    | 2,748  | 
 
  |    | 2,634  | 
 
  |  7.20%(a)  |    | March 2039  |    | 2,603  | 
 
  |    | 2,903  | 
 
  |  6.50% U.K. pound(b)  |    | June 2038  |    | 2,459  | 
 
  |    | 2,407  | 
 
  |  5.95%  |    | April 2037  |    | 2,085  | 
 
  |    | 2,086  | 
 
  |  4.55% euro  |    | May 2017  |    | 1,390  | 
 
  |    | 1,384  | 
 
  |  5.50%  |    | February 2016  |    | 1,033  | 
 
  |    | 1,048  | 
 
  |  5.50%(c)  |    | February 2014  |    | —  | 
 
  |    | 1,832  | 
 
  |  4.75% euro(d)  |    | December 2014  |    | —  | 
 
  |    | 1,284  | 
 
  |  Notes and other debt with a weighted-average interest rate of 5.47%(e)  |    | 2021–2043  |    | 4,810  | 
 
  |    | 3,403  | 
 
  |  Notes and other debt with a weighted-average interest rate of 4.70%(f)  |    | 2016–2018  |    | 3,683  | 
 
  |    | 2,254  | 
 
  |  Foreign currency notes and other foreign currency debt with a weighted- average interest rate of 3.02%(g)  |    | 2015-2016  |    | 628  | 
 
  |    | 771  | 
 
  |  Long-term debt  |    |    |    | $  | 30,462  | 
 
  |    | $  | 31,036  | 
 
  |  Current portion of long-term debt (not included above)  |    |    |    | $  | 2,060  | 
 
  |    | $  | 2,449  | 
 
  |  
  |  |  (a)   | Instrument is callable by us at any time at the greater of 100% of the principal amount or the sum of the present values of the remaining scheduled payments of principal and interest discounted at the U.S. Treasury rate plus 0.50% plus, in each case, accrued and unpaid interest.  |  
  |  |  (b)   | Instrument is callable by us at any time at the greater of 100% of the principal amount or the sum of the present values of the remaining scheduled payments of principal and interest discounted at a comparable government bond rate plus 0.20% plus, in each case, accrued and unpaid interest.  |  
  |  |  (c)   | At December 31, 2013, the note was called.  |  
  |  |  (d)   | At December 31, 2013, the note has been reclassified to Current portion of long-term debt.  |  
  |  |  (e)   | Contains debt issuances with a weighted-average maturity of approximately 24 years.  |  
  |  |  (f)   | Contains debt issuances with a weighted-average maturity of approximately 4 years.  |  
  |  |  (g)   | Contains debt issuances with a weighted-average maturity of approximately 2 years.  |  
  |