Mexican Petroleum F-4 Registration of securities (foreign)

Exhibit 12.2

PETROLEOS MEXICANOS’ SUBSIDIARY ENTITIES AND SUBSIDIARY COMPANIES

Computation of ratio of earnings to fixed charges

(In Thousands of Mexican pesos)

	For the period ended
	March 31, 2012			March 31, 2011
IFRS
Fixed Charges(1):
Interest capitalized during the period		759,634			545,197
Interest expense		14,190,860			11,909,202
Total interest cost		14,950,494			12,454,400
Total Fixed Charges		14,950,494			12,454,400
Net income		33,881,143			1,537,663
Hydrocarbon Income Tax (IRP)		1,795,817			3,725,129
Income Tax and Others		845,435			323,132
Cumulative effect of adoption of new accounting standards		—			—
Profit sharing in subsidiaries and affiliates (income from equity investees)		158,695			303,236
Pretax income from continuing operations before income from equity investees		36,681,090			5,889,161
Fixed Charges(1)		14,950,494			12,454,400
Amortization of interest capitalized		30,385			21,808
Dividends received on investments in shares		—			—
Interest capitalized during the period		(759,634	)		(545,197	)
Earnings		50,902,335			17,820,172
Amount by which fixed charges exceed earnings		(35,951,841	)		(5,365,772	)
Ratio of earnings to fixed charges		3.4047			1.4308

⁽¹⁾  These figures do not include rental expense.