Colombia's black market in foreign exchange
研究了1967年哥伦比亚第444号法令限制外汇获取后催生的黑市，该市场到1988年交易额达约25亿美元；毒品走私繁荣压低了黑市汇率并消除了溢价，尽管官方市场开放，黑市仍因走私者地下交易需求而持续存在。
Decree Law 444 in 1967 heavily restricted access to foreign exchange by Colombian residents. This policy spurred the development of a large black market, which had grown to about US$2.5 billion of transaction value per year by 1988. Soon after the restrictive policies were imposed, marijuana and then cocaine smuggling became large industries in Colombia; this narcotics boom has apparently driven down the black market exchange rate and largely eliminated the exchange rate premium that is usual for such markets. While Colombia's government has opened up the official foreign exchange market in the early 1990s, the black market is expected to continue to thrive, due to the smugglers' need to resort to underground means for transacting their business.