Exhibit 7.1
    (1 of 2)
  PETROLEOS
    MEXICANOS SUBSIDIARY ENTITIES AND SUBSIDIARY COMPANIES
  Computation
    of ratio of earnings to fixed charges
 (in
    thousands of
    pesos)(1)
  2008


2007


2006


2005


2004Mexican Financial Reporting StandardsFixed
    Charges(2):Interest capitalized in fixed assets


1,057,440



5,350,849



6,996,305



5,540,983



4,841,751Interest expense


73,883,856



57,847,569



46,099,472



57,146,232



35,437,454Total interest cost


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Total Fixed Charges


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Net income


(112,076,444
)


(18,307,569
)


46,953,205



(82,357,983
)


(28,443,617
)Hydrocarbon Income Tax (IRP)


1,582,910



6,030,367



4,914,859



2,135,245



Income Tax and Others


8,885,312



3,226,241



4,605,044



3,981,678



2,076,693Cumulative effect of adoption of new accounting standards














(1,905,868
)


(11,679,643
)Profit sharing in subsidiaries and affiliates (income from
    equity investees)


(1,965,213
)


(5,545,054
)


(10,073,577
)


(8,658,665
)


(3,605,792
)Pretax income from continuing operations before income from
    equity investees


(99,643,009
)


(14,596,015
)


46,399,531



(86,805,593
)


(41,652,359
)Fixed
    Charges(2):


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Amortization of interest capitalized


42,298



214,034



279,852



221,639



193,670Distribute income of investments shares


2,923,216



3,558,680



5,876,453



5,486,425



1,274,764Interest capitalized in fixed assets


(1,057,440
)


(5,350,849
)


(6,996,305
)


(5,540,983
)


(4,841,751
)Earnings


(22,793,639
)


47,024,268



98,655,308



(23,951,297
)


(4,746,471
)Amount by which fixed charges exceed earnings


97,734,935



16,174,150







86,638,512



45,025,676Ratio of earnings to fixed charges










1.8581     (1)
    
    Figures for 2004, 2005 and 2006 are
    stated in constant pesos as of December 31, 2007. Figures
    for 2008 are stated in constant pesos as of December 31,
    2008.(2)
    
    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
 (in
    thousands of
    pesos)(1)
  2008


2007


2006


2005


2004U.S. GAAPFixed
    Charges(2):Interest capitalized in fixed assets


559,607



7,797,815



8,659,013



6,321,963



5,832,766Interest expense


74,381,689



55,400,603



44,436,764



56,365,252



34,446,439Total interest cost


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Total Fixed Charges


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Net income


(67,765,607
)


(32,642,076
)


56,722,446



(79,791,073
)


(14,515,640
)Hydrocarbon Income Tax (IRP)


1,570,288



5,967,879



4,840,082



2,577,913



Income Tax and Others


8,885,312



3,226,241



4,605,044



3,981,678



2,076,693Cumulative effect of adoption of new accounting standards














(1,905,868
)


(11,679,643
)Profit sharing in subsidiaries and affiliates (income from
    equity investees)


(1,815,570
)


(5,791,312
)


(7,078,235
)


(7,828,486
)


(4,360,285
)Minority interest


140,652



6,089



54,789



(1,159,233
)


202,773Pretax income from continuing operations before income from
    equity investees


(59,266,229
)


(29,233,179
)


59,144,126



(84,125,069
)


(28,276,102
)Fixed
    Charges(2):


74,941,296



63,198,418



53,095,777



62,687,215



40,279,205Amortization of interest capitalized


22,384



311,913



346,361



252,879



233,311Distribute income of investments shares


2,923,216



3,558,680



5,876,453



5,486,425



1,274,764Interest capitalized in fixed assets


(559,607
)


(7,797,815
)


(8,659,013
)


(6,321,963
)


(5,832,766
)Earnings


18,061,060



30,038,017



109,803,704



(22,020,513
)


7,678,412Amount by which fixed charges exceed earnings


56,880,236



33,160,401







84,707,728



32,600,793Ratio of earnings to fixed charges










2.0680     (1)
    
    Figures for 2004, 2005 and 2006 are
    stated in constant pesos as of December 31, 2007. Figures
    for 2008 are stated in constant pesos as of December 31,
    2008.(2)
    
    These figures do not include rental
    expense.