1.   Economists say trade lags foreign exchange movements by six to nine months.

2.   Fabricated product prices, which are locked in by contracts, typically lag movement in ingot prices by as much as three months.

3.   Revenue from tourism tends to lag currency movements because people book their holidays up to six months in advance.

4.   The prices of fabricated products, which are locked in by contracts, typically lag movement in ingot prices by as much as three months.

5.   Trade generally lags foreign exchange movements by six to nine months.