NEW YORK ( TheStreet) -TheStreet Ratings' stock model downgraded Tam SA ( TAM) to 'Sell' from 'Hold'. This South American airline which connects Miami and New York to Brazil, Paraguay, Argentina, and Chile looks to be flying into a stormy earnings season. TheStreet Ratings released rating changes on only one U.S. common stocks for July 13, 2010. Just one stock has been downgraded and no stocks have been upgraded by our stock model. TAM Airlines has experienced a steep decline in earnings per share in the most recent quarter in comparison to its performance from the same quarter a year ago. This company has reported somewhat volatile earnings recently and may report a decline in earnings in the coming year. For the next year, the market is expecting a contraction of 90% in earnings ($0.25 versus $2.49). Net operating cash outflow at TAM Airlines of $207 million has shown significantly deterioration when compared to the same quarter last year. The net income flipped to a loss of $32.6 million from a gain of $7.4 million when compared to the same quarter one year ago. TAM's gross profit margin for the first quarter of its fiscal year 2010 has significantly decreased when compared to the same period a year ago. Even though sales increased, the net income has decreased, representing a decrease to the bottom line. TAM has weak liquidity. Currently, the Quick Ratio is 0.92 which shows a lack of ability to cover short-term cash needs. Overall, key liquidity measurements indicate that the company is in a position in which financial difficulties could develop in the future. Even though the stock's performance recently has been a positive, the TheStreet Ratings' stock model judges that the financial risks have increased thus prompting the downgrade to a 'Sell' recommendation. -- Reported by Kevin Baker in Jupiter, Fla. For additional Investment Research check out our Ratings Research Center.