NEW YORK ( TheStreet) -- Teradata ( TDC) was the worst-performing stock in the S&P 500 on Friday morning. The S&P 500 was falling more than 14 points, or 1.06%, to 1,353. Shares of Teradata dropped 9.63% to $65.63. Rival Informatica ( INFA) reported Thursday preliminary second-quarter earnings of 27 cents a share to 28 cents a share. Analysts, on average, were anticipating earnings of 37 cents a share. Bloomberg reported BMO analyst Karl Keirstead said Informatica's earnings move "will likely raise concerns about Teradata, Tibco, Pegasystems, Oracle and IBM." Teradata trades at an estimated price-to-earnings ratio for next year of 30.9 times; the average among its peers is 31.87. For comparison, Oracle ( ORCL) has a lower forward P/E of 14.71. Eleven of the 20 analysts who cover Teradata rated it buy; nine analysts gave the stock a hold rating. The stock has risen 35.31% year to date.