Politécnico GrancolombianoVersion en ligne Review activity Unity 3 Week 6 CULTURE AND REGIONAL ECONOMY OF AMERICA par POLITÉCNICO GRANCOLOMBIANO EDUCACIÓN VIRTUAL 1 It was a program in which the United States granted duty-free entry of merchandise to Bolivia, Colombia, Ecuador and Peru. Pistas 1 it was enacted into law on 4 December 1991. 2 The objective of the ATPA was to combat drug production and trafficking by offering trade benefits to help countries diversify and strengthen legitimate industries.