With the benefit of hindsight, the world always seems to be totally explicable. Projections for the future, in contrast, are full of uncertainties. No one can be sure what the future folds, even if economists offer forecasts apparently accurate to at least one decimal place. In trust, forecasters behave like hers of wildebeest, heading off in one direction or another without ever really knowing why. Far better, it seems, for everyone to be wrong in exactly the same way than to take the risk of standing out from the pack.

Yet, the forecasting consensus has missed some of the big stories in recent years. As late as September 2008, forecasters on average still thought the US would enjoy growth of over one per cent in 2009 as opposed to the eventual more than three per cent contraction. In 2011, forecasters thought the eurozone was embarking on a sustained cyclical recovery – prompting the European Central Bank to raise interest rates – even though a sovereign bond crisis was just around the corner.

And, at the beginning of 2013, forecasters competed to revise up their forecasts for Japanese growth, completely convinced that Abenomics would transform Japan’s economic prospects. It didn’t. Remarkably, the consensus growth forecast for Japan in 2014 is now back to one per cent, exactly where it was before Abenomics was first announced.

Forecasting tail risks is no easy task, one reason why the global financial crisis was only spotted with the help of rear-view mirrors. Our risks are divided into three main categories: (i) growth risks; (ii) policy risks; and (iii) market risks.

Forecasting tail risks is no easy task, one reason why the global financial crisis was only spotted with the help of rear-view mirrors

Many of the growth risks are on the downside – associated with fault-lines in both the eurozone and China – but, with promises of structural reform, there may be some surprising rays of light in parts of the emerging world.

Policy risks are mostly associated with central banks changing tack in a world fundamentally different to how it used to be pre-financial crisis: helicopters and premature tightening are both potential sources of instability.

As for market risks, our big worries are an excessively strong dollar, a return of oil price strength and a liquidity black hole.

Other risks didn’t quite make it into the ‘Top 10’ but there are some that are still worth mentioning. On the upside, maybe the US economy will finally return to its earlier vibrancy, in the process becoming once again the world’s ‘consumer of last resort’.

On the downside, the rouble collapse raises the spectre of Russian capital controls while Latin America seems economically to be going from bad to worse. Then there are broader political themes, not least the rise in support for anti-European and anti-immigration political parties throughout Europe.

Stephen King is chief global economist, and Fredrik ­Nerbrand, global head of asset allocation, HSBC Bank plc.