When investing, it pays to follow the money and, right now, it is flooding into the corporate sector. AllianceBernstein economist Joseph Carson has calculated that US corporations, excluding finance companies, are sitting on a record pile of liquid assets, totalling $1.8 trillion.

The ratio of liquid assets to short-term liabilities is nearly 50% - the highest since the 1950s. Cash as a proportion of total assets within the S&P 500 index stood at a 35-year high earlier this year.