Income Investor pick US Bancorp (NYSE: USB) emerged relatively unscathed from a treacherous credit environment, and reported rather solid fourth-quarter earnings.

In the same week that Citigroup (NYSE: C) announced a $9.8 billion quarterly loss on account of a $18.1 billion write-off, and Merrill Lynch (NYSE: MER) raised $6.6 billion of capital to shore up a weakened balance sheet, US Bancorp announced a mere $107 million valuation loss on asset-backed commercial paper.

Excluding the $107 million write-off and a $215 million legal litigation charge involving a Visa lawsuit, earnings per share came in essentially flat from the prior-year period. Other metrics also held up impressively in a tough environment. Net interest margin -- a profitability measurement for banks -- clocked in at 3.51%, slipping 5 basis points year over year, but up 7 basis points sequentially. Non-interest income, such as trust and management fees, showed strong growth. In addition, the efficiency ratio came in at 54.7%. However, if one excludes the legal and valuation charges, the efficiency ratio remains an impressive 47.2%, or flat with the fourth quarter of last year.

Credit quality also held up in an increasingly treacherous environment. In an environment where Capital One (Nasdaq: COF) and even American Express (NYSE: AXP) are feeling the heat of delinquencies and charge-offs, US Bancorp's credit card net charge-off ratio of 3.29% remained extremely low. Net charge offs for US Bancorp as a whole increased five basis points sequentially to 59 basis points.

Another interesting comment US Bancorp made during the quarter was that its mortgage banking unit was benefiting from a "flight to quality." After all, only 2.7% of US Bancorp's loans are subprime loans. In fact, US Bancorp's conservative management and rock-solid balance sheet should allow it to be a market share beneficiary as weaker competitors continue to falter.

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Fool contributor Emil Lee is an analyst and a disciple of value investing. He doesn't own shares in any of the companies mentioned above. Emil appreciates your comments, concerns, and complaints. The Motley Fool has a disclosure policy.