Exhibit 7.1
    (1 of 2)
  PETROLEOS
    MEXICANOS SUBSIDIARY ENTITIES AND SUBSIDIARY COMPANIES
  Computation
    of ratio of earnings to fixed charges
 (Figures
    stated in thousands of Mexican pesos as of December 31,
    2007 purchasing power)
  2007


2006


2005


2004


2003Mexican Financial Reporting StandardsFixed
    Charges(1):Interest capitalized in fixed assets


5,350,849



6,996,305



5,540,983



4,841,751



8,503,817Interest expense


57,847,569



46,099,472



57,146,232



35,437,454



27,563,053Total interest cost


63,198,418



53,095,777



62,687,215



40,279,205



36,066,870Total Fixed Charges


63,198,418



53,095,777



62,687,215



40,279,205



36,066,870Net income


(18,307,569
)


46,953,205



(82,357,983
)


(28,443,617
)


(47,697,707
)Hydrocarbon Income Tax (IRP)


6,030,367



4,914,859



2,135,245







Income Tax and Others


3,226,241



4,605,044



3,981,678



2,076,693



4,616,022Cumulative effect of adoption of new accounting standards










(1,905,868
)


(11,679,643
)


2,362,076Profit sharing in subsidiaries and affiliates (income from
    equity investees)


(5,545,054
)


(10,073,577
)


(8,658,665
)


(3,605,792
)


(1,044,127
)Pretax income from continuing operations before income from
    equity investees


(14,596,015
)


46,399,531



(86,805,593
)


(41,652,359
)


(41,763,736
)Fixed
    Charges(1):


63,198,418



53,095,777



62,687,215



40,279,205



36,066,870Amortization of interest capitalized


214,034



279,852



221,639



193,670



340,153Distribute income of investments shares


3,558,680



5,876,453



5,486,425



1,274,764



315,889Interest capitalized in fixed assets


(5,350,849
)


(6,996,305
)


(5,540,983
)


(4,841,751
)


(8,503,817
)Earnings


47,024,268



98,655,308



(23,951,297
)


(4,746,471
)


(13,544,641
)Amount by which fixed charges exceed earnings


16,174,150







86,638,512



45,025,676



49,611,511Ratio of earnings to fixed charges






1.8581      (1)
    
    These figures do not include rental
    expense




---



##### 



Exhibit
    7.1
    (2 of 2)
  PETROLEOS
    MEXICANOS SUBSIDIARY ENTITIES AND SUBSIDIARY COMPANIES
  Computation
    of ratio of earnings to fixed charges
 (Figures
    stated in thousands of Mexican pesos as of December 31,
    2007 purchasing power)
  2007


2006


2005


2004


2003U.S. GAAPFixed
    Charges(1):Interest capitalized in fixed assets


7,797,815



8,659,013



6,321,963



5,832,766



9,335,023Interest expense


55,400,603



44,436,764



56,365,252



34,446,439



26,754,192Total interest cost


63,198,418



53,095,777



62,687,215



40,279,205



36,089,215Total Fixed Charges


63,198,418



53,095,777



62,687,215



40,279,205



36,089,215Net income


(32,642,076
)


56,722,446



(79,791,073
)


(14,515,640
)


(77,816,590
)Hydrocarbon Income Tax (IRP)


5,967,879



4,840,082



2,577,913







Income Tax and Others


3,226,241



4,605,044



3,981,678



2,076,693



4,616,022Cumulative effect of adoption of new accounting standards










(1,905,868
)


(11,679,643
)


2,362,076Profit sharing in subsidiaries and affiliates (income from
    equity investees)


(5,791,312
)


(7,078,235
)


(7,828,486
)


(4,360,285
)


(391,220
)Minority interest


6,089



54,789



(1,159,233
)


202,773



31,370Pretax income from continuing operations before income from
    equity investees


(29,233,179
)


59,144,126



(84,125,069
)


(28,276,102
)


(71,198,342
)Fixed
    Charges(1):


63,198,418



53,095,777



62,687,215



40,279,205



36,089,215Amortization of interest capitalized


311,913



346,361



252,879



233,311



373,401Distribute income of investments shares


3,558,680



5,876,453



5,486,425



1,274,764



315,889Interest capitalized in fixed assets


(7,797,815
)


(8,659,013
)


(6,321,963
)


(5,832,766
)


(9,335,023
)Earnings


30,038,017



109,803,704



(22,020,513
)


7,678,412



(43,754,860
)Amount by which fixed charges exceed earnings


33,160,401







84,707,728



32,600,793



79,844,075Ratio of earnings to fixed charges






2.0680      (1)
    
    These figures do not include rental
    expense