Andrew Witty, the 43-year-old who on Wednesday made his first results presentation as the new boss of GSK, makes for a rather unusual chief executive. That is less because of his youth than his Britishness. The trend for FTSE 100 companies, which tend to have a high proportion of their sales in markets outside the UK, is to source their senior-most executive from overseas. Forty per cent of the largest 100 companies listed in the UK now have non-British chief executives, according to unpublished research by Credit Suisse, reflecting a remarkable cultural shift that has taken place within scarcely a generation.

With the average chief executive lasting a little under 5½ years, about 18 of the index’s constituents could be expected to change top dog in a normal year, and probably more in a downturn. It is therefore hardly inconceivable that a majority of the largest UK-listed companies will have non-British chief executives within a few years. The trend reflects not just the globalisation of the biggest UK-listed companies, but also the attractiveness of London’s capital markets to groups such as Kazakhmys, Vedanta and Xstrata. Even if this influx has so far been mostly limited to resources groups, others will surely follow suit.