Using this method, the stocks that make up the FTSE 100 now look less attractive than a few months ago - their average p/e ratio is now 13.6, compared with 9.6 last year.

So after reaching a 13-year high of 6840 on Wednesday, the FTSE 100 dropped 2.1% on Thursday and fell another 0.6% or 42.45 points on Friday to 6654.34.

A 2% drop in the FTSE 100 is not that unusual, but they have become more frequent in recent years. On Thursday the leading index dropped 2.1%, its biggest daily percentage fall for a year, as investors fretted about a possible end to quantitative ...

Worries the US was closer to bringing its economic stimulus measures to an end and concern over the state of the Chinese economy triggered a huge global sell-off today, with the FTSE 100 falling from its highest level in thirteen years. London's blue ...

A day after the FTSE 100 came within 90 points of its December 1999 peak, the index slumped 2.1%, down 143.48 points at 6696.79.

So the FTSE 100 finished down 143.48 points at 6696.79, a 2.1% decline which marks its worst daily performance since exactly a year ago.

Until today, the FTSE 100 had risen 16pc so far this year and some had feared a correction - a sharp, rapid fall in the market - was overdue.

According to Ingram's calculations, over the fourteen years since the FTSE 100 was last at 6800, its companies have paid out the equivalent of another 2400 in dividends.

So having climbed as high as 6875, the FTSE 100 finished 36.4 points higher at 6840.27, just 90 points from its peak of 6930 reached on 30 December 1999.

Should the FTSE 100 finish above 6,798.1 - its close on September 4, 2000 - then it would be at its best level since December 30, 1999, when it reached an all-time high.