When US Federal Reserve officials meet in September to decide whether to raise interest rates, they will have a plethora of economic data to ponder. But if they want to get a novel twist on the current state of finance, they should take a glance at the balance sheets of American companies.

For these days, it seems that a subtle — and largely unnoticed — shift is under way in how American companies are placing their spare funds. And, like so much in western finance today, it is a trend that is partly driven by some unexpected side effects of a low interest rate world.

To understand this, take a look at a survey recently released by the Association of Financial Professionals on the behaviour of corporate treasurers. This analysis starts by highlighting a point that is well known: namely that holdings of corporate cash have recently swelled, because company profits have surged, but investment has remained relatively low.