Pick the odd one out: Basketball, badminton, baseball, boxing or bridge. Yes, bridge is not recognised as a sport, a situation its sedentary devotees are currently fighting in the High Court to have rectified. Could foreign exchange claim the same status? Well, at least it can sometimes be interesting to watch.

That was the case yesterday, with the safe-haven currencies heading higher as global share prices sank. Other than the unfolding story about covert software in Volkswagen diesel engines, which undoubtedly exerted a downward pressure on equities as a whole, there were no significant data or news to drive the move. It was more a matter of investors continuing to agonise over the timing, scale and effect of the Federal Reserve rate increase which most of them believe is imminent.

The US dollar was one of the main beneficiaries, strengthening by more than a cent and a half against sterling and three quarters of a cent against the euro. Not far behind, the Swiss franc added a cent and a quarter. The pound is half a cent lower against the euro and down by an average of -0.4% on the day.

Currency action went from interesting to exciting early this morning when the first of the Chinese purchasing managers' indices came in at a provisional 47.0 for the manufacturing sector. It was the lowest reading in six years and marked the eleventh successive month of decline.

Investors are acutely conscious of economic developments in China, not because they have any direct interests in China itself but because of the influence the world's second-biggest economy has on everywhere else. The softer PMI reading this morning knocked a cent and a half off the Australian dollar and sent the Japanese currency one and a half yen higher, making it the day's top performer.

The euro and the US dollar both felt the benefit of the safe-haven buying. Sterling was less fortunate. As usual, when investors want to move quickly they go where the liquidity is greatest and those currencies are, in order, the US dollar, the euro, the Japanese yen and the pound. So sterling was left behind in the rush.

After two days of ecostat scarcity, today brings a relative deluge. Although none will have the individual impact of the Chinese PMI, together they could make a difference. The provisional PMI readings will be of particular interest to investors, as will the ECB president's testimony to the European Parliament.

Only the French manufacturing sector is expected spoil a set of otherwise positive PMIs from Euroland and the States. There are retail sales figures from Canada after lunch and balance of trade data from New Zealand tonight.

Central banks will also be in the frame, starting with the South African Reserve Bank, which is expected to keep its benchmark interest rate at 6%. This afternoon the European Central Bank's Mario Draghi answers question from the European Parliament and the Fed's Dennis Lockhart will be speaking later.