For a third straight day, the Dow Jones Industrial Average closed at all-time highs, with the S&P 500 Index (SNPINDEX:^GSPC) also posting gains. Good news from the labor markets, which saw fewer people filing for unemployment benefits than expected, combined with good numbers from Federal Reserve bank stress tests, drove markets higher. Unfortunately, three companies in the S&P had a particularly rough time today.

Retailer Ross Stores (NASDAQ:ROST) disclosed some nasty numbers today, and slid 7.5%, to finish the day as the worst-performing S&P component. Same-store sales figures for February declined 1%, when investors were looking for a 1.1% increase. Even though the CEO deflected blame for the miss by invoking delayed tax refunds as the cause, the fact that the health of the company is so dependent on prompt tax refunds for success is worrisome. Ross will have a chance to redeem itself at its next quarterly earnings announcement two weeks from today. 

Data solutions company Teradata (NYSE:TDC) took a heavy hit today, as well, as shares lost 3.1% after an analyst tempered expectations for the stock. By issuing a $70 price target and a neutral rating, the UBS announcement continues a trend of diminishing outlooks by Wall Street analysts: Barclays has twice decreased its target price for Teradata this year alone, going from a $85 target to a $73 price target in a month's time. 

Telecom services company CenturyLink (NYSE:CTL) lost 1.5%, a slide entirely explicable due to the fact that shareholders on record as of yesterday's close are entitled to the quarterly dividend payment. At a 6.2% annual clip, that quarterly dividend comes out to $0.54 per share. Not surprisingly, the stock fell $0.53  today, as investors in the stock for the next dividend payment can sell the stock and still receive the payout.