In traffic forecasting two methods can be resorted to, which as may appear are not mutually exclusive.
These are :-
----- trend analysis and extrapolation.
----- trade projections based on economy of the country and are done on the basis of actual economics parameters.
Both methods applied mechanically and in isolation can lead to very unrealistic figures. Normally trade forecasting will start with the trade statistics of the previous years preferably in both value and volume terms.
Port statistics may be helpful in other cases but in the context of LLCs where the serving ocean ports may not have the country-wise exports, this method will not help to allow analysis of trend, a run of figures is needed and the period should be preferably at least as long as the forecasting period.
The economists approach in trade forecasting would tend to categorize commodities according to their economic properties .
A clear cut distinction has to be made between exports and imports. The export would be divided into agricultural and industrial products, each group being further broken down into main commodities.
Similarly , imports can also be divided according to their economic properties .
Such as :-
----- Consumer goods.
----- Intermediate products.
----- Capital goods.
However as already mentioned, trend extrapolation used for long term forecasting can be extremely misleading. Therefore after acquiring a general idea of growth trends, economic parameters may be introduced to formulate more realistic relationship would be quite different for imports and exports.
