The ratings on Exxon Mobil Corp. reflect the company's outstanding competitive position in all facets of the oil and gas industry and conservative financial policies. Although Irving, Texas-based Exxon Mobil operates in many different segments of the energy industry, its exploration and production (E&P) unit by far is the most important contributor to profitability and cash flow and is the driver of future growth. Exxon Mobil's proved reserves total about 22 billion barrels of oil equivalent (boe), which comprises one of the largest resource bases among both national and nonnational oil companies. Depletion risks are mitigated by a long reserve life (13.9 years) and a large resource base (estimated at 72 billion boe) from which future commercial projects are likely
