Wall Street's principal blue-chip index soared 70.24 points (0.88 per cent) yesterday fuelled by developments on the bond market and WorldCom's bid to buy telecommunications giant MCI (see opposite page). It is the first time the Dow Jones closed above the 8000 mark since August 20th.

On the bond market, the average yield of benchmark, 30-year Treasury bonds was 6.33 per cent against 6.39 per cent on Tuesday. Buying was spurred by reports of a slowdown in US economic growth for September. The National Association of Purchasing Managers headline index fell to 54.2 in September from 56.8 in August.

WorldCom's surprise 30 billion-dollar bid for MCI gave MCI and WorldCom rival British Telecommunications (BT) a boost. MCI rose 5 7/8 to 35 1/4 and BT rose 5 7/8 to 72 1/2 while WorldCom dipped one dollar to 34 3/8