Come April 10, a new-avatar 30-share BSE Sensex will be flashed on brokers' trading screens. Four stocks-idbi, Tata Chemicals, Indian Hotels and Tata Power-will be replaced with Zee Telefilms, Satyam Computers, Reliance Petroleum and Dr Reddy's Laboratories. The change in the Sensex's composition looks like another blow to the Old Economy, and a fillip to the New.