MARK BARNES: Countries and companies now beholden to global ebbs and flows
A tweet from across the world, a market crash a million miles away … these forces now wash up on our shores, thanks to technology
It is no longer unusual for stock market indices to have big intraday moves, either way. Even the mature, highly trade S&P 500 index (a proxy for aggregate US corporate performance) regularly moves up or down by a couple of percent a day. The values of individual companies can move by multiples of that. Sometimes there are valid facts (such as an earnings update or discovered fraud) that can cause extreme changes in company values forever. We expect that. But in the absence of material factual change, now reasons beyond fundamental valuation metrics are causing unusually big moves. Moves between indices and across geographies are likewise getting bigger, inconsistent and less easy to explain, let alone expect or predict. Tried and tested valuation techniques are no longer universally valid (though their purpose wasn’t ever to explain short-term variations). Like it or not, companies and countries operate less and less in a vacuum. External factors and the behaviour of others are pla...