Benjamin Graham also says

I was about to chuck out the Benjamin Graham lecture notes - I mean who keeps 47year old typescripts , even if they did originally cost 50c?

But in a handful of pages Graham not only discussed the weight of asset classes in of a portfolio [risky v nonrisky, see last blog], he also looked at what you should buy and when to rebalance.

'Use a 50-50 division between stock and bonds. When the market level of the stocks rises to a point where they constitute 55% of the total or maybe 60%, you would then sell out enough to bring your proportion back to 50% putting the proceeds, back into bonds or saving banks.'

Graham goes on to discuss various similar 'formula plans' -

'The main need here is for the investor to select some rule which seems to be suitable for his point of view, one which will keep him out of mischief and one, I insist, which will always maintain some interest in common stocks regardless of how high the market level goes'

Graham's point being that if you missed out on a bubble (my word) your disappointment (his word) would have been so great -

'as probably to ruin you from the standpoint of intelligent investing for the rest of you life.'

A final word on stock selection:

'there is no indication that the investor can do better than the market averages by making his own selection or by taking expert advice.'

When Graham wrote this in 1963 the first index funds were years away.