##### 



Exhibit 12
 Potash Corporation of Saskatchewan Inc.
Ratio of Earnings to Fixed Charges
(in millions of U.S. dollars, except ratio amounts)
(unaudited)
 Year ended December 312006
    
    
    2005
    
    
    2004
    
    
    2003
    
    
    2002Canadian GAAPNet income (loss)
    
    $
    631.8
    
    
    $
    542.9
    
    
    $
    298.6
    
    
    $
    (126.3
    )
    
    $
    53.6Income taxes
    
    
    158.1
    
    
    
    267.4
    
    
    
    131.7
    
    
    
    (20.6
    )
    
    
    30.2Share of earnings of equity investees
    
    
    (54.4
    )
    
    
    (52.1
    )
    
    
    (30.9
    )
    
    
    (12.4
    )
    
    
    (5.3
    )Fixed charges
    
    
    183.5
    
    
    
    149.1
    
    
    
    132.4
    
    
    
    117.8
    
    
    
    102.7Distributed income of equity investees
    
    
    29.9
    
    
    
    18.6
    
    
    
    8.7
    
    
    
    4.0
    
    
    
    Interest capitalized
    
    
    (19.1
    )
    
    
    (5.7
    )
    
    
    (2.5
    )
    
    
    (1.5
    )
    
    
    (4.2
    )Total Earnings Available for Fixed Charges
    
    $
    929.8
    
    
    $
    920.2
    
    
    $
    538.0
    
    
    $
    (39.0
    )
    
    $
    177.0Fixed ChargesInterest expensed and capitalized
    
    $
    163.6
    
    
    $
    127.2
    
    
    $
    112.8
    
    
    $
    105.7
    
    
    $
    92.0Amortization of debt issue costs
    
    
    1.0
    
    
    
    2.2
    
    
    
    2.2
    
    
    
    2.1
    
    
    
    1.9Estimated portion of rent expense representing interest
    
    
    18.9
    
    
    
    19.7
    
    
    
    17.4
    
    
    
    10.0
    
    
    
    8.8Total Fixed Charges
    
    $
    183.5
    
    
    $
    149.1
    
    
    $
    132.4
    
    
    $
    117.8
    
    
    $
    102.7Ratio of Earnings to Fixed Charges
    
    
    5.07
    
    
    
    6.17
    
    
    
    4.06
    
    
    
    
    (1)
    
    
    1.72
 
 (1)
    
    Earnings were inadequate to cover fixed charges by $156.8 million for the year ended December 31, 2003. U.S. GAAPNet income (loss)
    
    $
    625.8
    
    
    $
    532.7
    
    
    $
    290.5
    
    
    $
    (84.2
    )
    
    $
    60.4Income taxes
    
    
    174.4
    
    
    
    288.0
    
    
    
    151.9
    
    
    
    7.4
    
    
    
    34.4Share of earnings of equity investees
    
    
    (54.9
    )
    
    
    (55.8
    )
    
    
    (30.9
    )
    
    
    (12.4
    )
    
    
    (5.3
    )Fixed charges
    
    
    183.5
    
    
    
    149.1
    
    
    
    132.4
    
    
    
    117.8
    
    
    
    102.7Distributed income of equity investees
    
    
    29.9
    
    
    
    18.6
    
    
    
    8.7
    
    
    
    4.0
    
    
    
    Interest capitalized
    
    
    (19.1
    )
    
    
    (5.7
    )
    
    
    (2.5
    )
    
    
    (1.5
    )
    
    
    (4.2
    )Total Earnings Available for Fixed Charges
    
    $
    939.6
    
    
    $
    926.9
    
    
    $
    550.1
    
    
    $
    31.1
    
    
    $
    188.0Fixed ChargesInterest expensed and capitalized
    
    $
    163.6
    
    
    $
    127.2
    
    
    $
    112.8
    
    
    $
    105.7
    
    
    $
    92.0Amortization of debt issue costs
    
    
    1.0
    
    
    
    2.2
    
    
    
    2.2
    
    
    
    2.1
    
    
    
    1.9Estimated portion of rent expense representing interest
    
    
    18.9
    
    
    
    19.7
    
    
    
    17.4
    
    
    
    10.0
    
    
    
    8.8Total Fixed Charges
    
    $
    183.5
    
    
    $
    149.1
    
    
    $
    132.4
    
    
    $
    117.8
    
    
    $
    102.7Ratio of Earnings to Fixed Charges
    
    
    5.12
    
    
    
    6.22
    
    
    
    4.15
    
    
    
    
    (2)
    
    
    1.83
 
 (2)
    
    Earnings were inadequate to cover fixed charges by $86.7 million for the year ended December 31, 2003.