Hanah Cho, The Baltimore Sun">

Constellation to be replaced on S&P 500 index

Constellation Energy Group

, which is being sold to Chicago-based

Exelon Corp.

, will be replaced on the S&P 500 index by a Houston wireless company.

Exelon is acquiring Constellation in a $7.9 billion deal that is waiting for approval from the Federal Energy Regulatory Commission.

S&P will announce the date when

Crown Castle International Corp.

is to replace Constellation on the index after the merger deal closes.