Quantitative models of import demand have revolved around numerical estimates of demand elasticities for a number of theoretical and practical reasons. Especially in Latin America, much of stimulus and direction of post war development is said to have originated out of reaction to the trade constraint.

The transformation of Puerto Rico from a sugar-monoculture began in the early 1950's and by 1963 created a diversified manufacturing export economy. During these years, gross domestic product more than doubled, while gross investment and exports nearly quadrupled (Table 1). The magnitude of the industrialization, as seen in the rise of the industrial share of GDP by 50% and the decline of the agricultural share by about the same extent, resulted in the doubling of per capita income while employment remained stable.