Exhibit 12
 Potash Corporation of Saskatchewan Inc.
Ratio of Earnings to Fixed Charges
(in millions of US dollars, except ratio amounts)
(unaudited)
 Year ended December 312010
    
    2009(1)
    
    2008(1)
    
    2007(1)
    
    2006(1)Canadian GAAPNet income
    
    $
    1,806.2
    
    
    $
    980.7
    
    
    $
    3,465.9
    
    
    $
    1,104.0
    
    
    $
    606.9Income taxes
    
    
    642.8
    
    
    
    79.2
    
    
    
    1,059.8
    
    
    
    416.7
    
    
    
    142.3Share of earnings of equity investees
    
    
    (174.3
    )
    
    
    (133.7
    )
    
    
    (255.8
    )
    
    
    (76.2
    )
    
    
    (54.4
    )Fixed
charges
    
    
    273.3
    
    
    
    255.9
    
    
    
    187.1
    
    
    
    187.5
    
    
    
    183.5Amortization of capitalized interest
    
    
    8.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Distributed income of equity investees
    
    
    78.5
    
    
    
    130.9
    
    
    
    89.1
    
    
    
    40.6
    
    
    
    29.9Interest capitalized
    
    
    (118.6
    )
    
    
    (68.2
    )
    
    
    (42.9
    )
    
    
    (21.8
    )
    
    
    (19.1
    )Total Earnings Available for Fixed Charges
    
    $
    2,516.4
    
    
    $
    1,244.8
    
    
    $
    4,503.2
    
    
    $
    1,650.8
    
    
    $
    889.1Fixed
ChargesInterest expensed and capitalized
    
    $
    247.9
    
    
    $
    227.2
    
    
    $
    160.9
    
    
    $
    165.4
    
    
    $
    163.6Amortization of debt issue costs
    
    
    4.9
    
    
    
    3.0
    
    
    
    1.8
    
    
    
    2.3
    
    
    
    1.0Estimated portion of rent expense representing interest
    
    
    20.5
    
    
    
    25.7
    
    
    
    24.4
    
    
    
    19.8
    
    
    
    18.9Total Fixed Charges
    
    $
    273.3
    
    
    $
    255.9
    
    
    $
    187.1
    
    
    $
    187.5
    
    
    $
    183.5Ratio of Earnings to Fixed Charges
    
    
    9.21
    
    
    
    4.86
    
    
    
    24.07
    
    
    
    8.80
    
    
    
    4.85US GAAPNet income
    
    $
    1,727.8
    
    
    $
    989.0
    
    
    $
    3,365.9
    
    
    $
    1,061.9
    
    
    $
    600.9Income taxes
    
    
    679.5
    
    
    
    51.8
    
    
    
    1,158.5
    
    
    
    452.8
    
    
    
    158.6Share of earnings of equity investees
    
    
    (173.4
    )
    
    
    (132.5
    )
    
    
    (254.8
    )
    
    
    (74.3
    )
    
    
    (54.9
    )Fixed charges
    
    
    273.3
    
    
    
    255.9
    
    
    
    187.1
    
    
    
    187.5
    
    
    
    183.5Amortization of capitalized interest
    
    
    8.5
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    
    Distributed income of equity investees
    
    
    78.5
    
    
    
    130.9
    
    
    
    89.1
    
    
    
    40.6
    
    
    
    29.9Interest capitalized
    
    
    (118.6
    )
    
    
    (68.2
    )
    
    
    (42.9
    )
    
    
    (21.8
    )
    
    
    (19.1
    )Total Earnings Available for Fixed Charges
    
    $
    2,475.6
    
    
    $
    1,226.9
    
    
    $
    4,502.9
    
    
    $
    1,646.7
    
    
    $
    898.9Fixed ChargesInterest expensed and capitalized
    
    $
    247.9
    
    
    $
    227.2
    
    
    $
    160.9
    
    
    $
    165.4
    
    
    $
    163.6Amortization of debt issue costs
    
    
    4.9
    
    
    
    3.0
    
    
    
    1.8
    
    
    
    2.3
    
    
    
    1.0Estimated portion of rent expense representing interest
    
    
    20.5
    
    
    
    25.7
    
    
    
    24.4
    
    
    
    19.8
    
    
    
    18.9Total Fixed Charges
    
    $
    273.3
    
    
    $
    255.9
    
    
    $
    187.1
    
    
    $
    187.5
    
    
    $
    183.5Ratio of Earnings to Fixed Charges
    
    
    9.06
    
    
    
    4.79
    
    
    
    24.07
    
    
    
    8.78
    
    
    
    4.90
 
 (1)
    
    Corrected as described in Note 32 to the
Companys consolidated financial statements.