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•	Exhibit 12 Computation of Ratio of Earnings to Fixed Charges

•	Exhibit 99.1

◦	Item 6. Selected Financial Data

◦	Item 7. Management’s Discussion and Analysis of Financial Condition and Results of Operations

◦	Item 7A. Quantitative and Qualitative Disclosures About Market Risk

◦	Item 8. Financial Statements and Supplementary Data

•	Exhibit 99.2. Schedule II — Valuation and Qualifying Accounts for each of the three years ended December 31, 2017

•	Exhibit 101.INS — XBRL Instance Document.

•	Exhibit 101.SCH — XBRL Taxonomy Extension Schema.

•	Exhibit 101.CAL — XBRL Taxonomy Extension Calculation Linkbase.

•	Exhibit 101.DEF — XBRL Taxonomy Extension Definition Linkbase.

•	Exhibit 101.LAB — XBRL Taxonomy Extension Label Linkbase.

•	Exhibit 101.PRE — XBRL Taxonomy Extension Presentation Linkbase.

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•	amounts and nature of future capital expenditures;

•	expansion and growth of our business and operations;

•	financial condition and liquidity;

•	business strategy;

•	estimates of proved oil and natural gas reserves;

•	reserve potential;

•	development drilling potential;

•	cash flow from operations or results of operations;

•	acquisitions or divestitures;

•	seasonality of our business; and

•	crude oil, natural gas and NGL prices and demand.

•	availability of supplies (including the uncertainties inherent in assessing, estimating, acquiring and developing future oil and natural gas reserves), market demand, volatility of prices and the availability and cost of capital;

•	inflation, interest rates, fluctuation in foreign exchange and general economic conditions (including future disruptions and volatility in the global credit markets and the impact of these events on our customers and suppliers);

•	the strength and financial resources of our competitors;

•	development of alternative energy sources;

•	the impact of operational and development hazards;

•	costs of, changes in, or the results of laws, government regulations (including climate change regulation and/or potential additional regulation of drilling and completion of wells), environmental liabilities, litigation and rate proceedings;

•	changes in maintenance and construction costs;

•	changes in the current geopolitical situation;

•	our exposure to the credit risk of our customers;

•	risks related to strategy and financing, including restrictions stemming from our debt agreements, future changes in our credit ratings and the availability and cost of credit;

•	risks associated with future weather conditions;

•	acts of terrorism;

•	other factors described in “Management’s Discussion and Analysis of Financial Condition and Results of Operations”; and

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•	additional risks described in our filings with the Securities and Exchange Commission (“SEC”).

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