American Airlines to join the S&P 500, replaces Allergan

S&P Dow Jones Indices says that American Airlines Group will soon be joining the S&P 500 index.

The Fort Worth, Texas, holding company for American Airlines and US Airways will be added to the index after the close of trading on Friday.

American Airlines is replacing health care company Allergan, which is being acquired by Actavis in a deal expected to close Tuesday.

Shares of American are up about 38 percent in the past year and added $1.83, or 3.6 percent, to $52.05 in extended trading.