NEW YORK (AP) ¿ Standard & Poor's said Thursday it has added insurer MetLife Inc. to the S&P 100, replacing health care products company Covidien Ltd., which will be ineligible for the index after it redomesticates to Ireland. In addition, Houston-based FMC Technologies Inc., which provides technology services to the energy industry, will replace Covidien in the S&P 500 index. Shares of companies added to the S&P 500 often rise, since many investment portfolios are linked to the index. At the same time, Columbia, Md.-based software provider Micros Systems Inc. will replace FMC in the S&P MidCap 400 and North Hollywood, Calif.-based physician group IPC The Hospitalist Company Inc. will replace Micros in the S&P SmallCap 600. Separately, Simmons First National Corp., which owns community banks in Arkansas, will replace Guaranty Financial Group Inc. in the S&P SmallCap 600. DTS Inc., which makes parts for entertainment systems, will also replace Irwin Financial Corp. in that index. As of Thursday's close, Guaranty Financial and Irwin Financial had market capitalizations of about $37 million and $35 million respectively, well below the index's minimum market cap of $200 million. Standard & Poor's is a subsidiary of McGraw-Hill Cos.