Biggest FTSE shake-up since dotcom bubble burst

Seven firms are set to fall out of the FTSE 100 in the biggest shake-up of the list of 100 largest PLCs since 2001.

Every quarter the FTSE 100 reshuffles the firms on the list – but today will see seven companies drop from the list – including Northern Rock, newspaper group Daily Mail & General Trust, DSG International (owner of Dixons, Currys and PC World), Tate & Lyle, builder Barratt and pub groups Mitchells & Butlers and Punch Taverns.

The change does have implications for investors and the firms' share prices as a number of investment funds are based on the top 100 firms – so those that make the list find their shares in greater demand, and prices rise, while those dropping out of the 100 often see share price falls.

The shake-up is the biggest for the FTSE since September 2001, when the dotcom bubble burst and eight firms fell out the list, and is being seen by many analysts as the credit crunch taking effect.

Firms entering the FTSE 100 from the FTSE 250 are set to include car insurer Admiral, Burberry, TUI (owner of travel agent Thompson), and security firm G4S.

Oil and gas company Cairn Energy, water firm Kelda Group and transport company FirstGroup, are all also expected to join the list.