Companies expelled from the FTSE 100 tend to laugh off their demotion as irrelevant. They argue that it doesn’t matter, that the index is an entirely artificial construct, that the impact on the share price from deserting tracker funds has been hugely exagerrated and that share prices are so volatile that they could easily be promoted back in again in three months time anyway.

All of this is perfectly true. But there is no getting away from the fact that membership of the Footsie confers prestige and gives companies visibility and credibility, not just with shareholders but with employees, suppliers, customers and ministers. It is human nature to prefer playing in the floodlit Premiership to the relative obscurity of a lesser league.

So although the seven relegated companies and their seven replacements will doubtless play down the significance of today’s Footsie shake-up, it fools nobody. Can it be mere coincidence that Thomas Cook timed its positive trading statement to yesterday, sending its shares soaring by 7 per cent, enough to elbow aside a hopeful Burberry at the very last moment?

Few of the new arrivals owe their growing size to organic brilliance. Mergers and acquisitions are responsible for the promotion of the train operator First Group and the travel agents TUI and Thomas Cook. Cairn Energy’s success is due to the rising oil price as well as its own efforts. However, G4S, the security guards group, and Admiral, the car insurer, do owe their promotion largely to organic growth.

The outcasts are a mixed bag. The credit crunch and property slowdown can fairly be blamed for the departures of Northern Rock, Barratt Developments and Mitchells & Butlers. Worries about slowing consumer spending may account for Punch Taverns and DSG International. The migration of newspaper readers and advertisers from the printed page to the internet explains some of Daily Mail & General Trust’s fall, while Tate & Lyle’s misfortunes are more company-specific.

Some of them have been ousted before and clawed their way back in. All of them except one look capable of doing so again. They are beefy, well established businesses, none of them facing insoluble problems.

The exception is Rock, which has tumbled to a lowly 331st in the league table of listed companies by size. Its return one day to corporate Britain’s most exclusive club will require more miraculous powers.

Times Recommends

• B&B shareholders forced into funding rescue
• John Lewis department store sales plunge 8.3%
• Families turn to credit to cover mortgage bills