When Panama joined the WTO in 1997, the government lowered tariffs to a maximum of 15%, except for a few agricultural products, and to an overall average of 12%, the lowest in the region. The revised import duty structure was significantly lower than the one negotiated for WTO accession and represented a substantial commitment to trade liberalization. In October 2012, the Trade Promotion Agreement (TPA) between the United States and Panama came into effect and reduced import duties to zero for 87% of the products in the tariff schedule, except some food and agricultural products, on which duties will reduce gradually over the course of the next fifteen years.