Air and water cargo transport mode substitutions among US customs districts

In the mid-1980s, under the impetus of deregulation, the competition between air and water cargo transportation showed a marked increase. The nature of this process and its empirical manifestation among the exports and imports of 30 commodity groups in six major American customs districts and the US as a whole is examined. The prevailing patterns of reliance upon each mode in 1987 and the changes that occurred between 1985 and 1987 are discussed. Finally, a logistic regression is offered and employed using 620 individual export and import commodities to determine what types of commodities are most likely to fluctuate between the transportation modes.