The Maldives remained largely unknown to tourists until the early 1970s. Only 189 islands are home to its 447,137 inhabitants. The other islands are used entirely for economic purposes, of which tourism and agriculture are the most dominant. Tourism accounts for 28% of the GDP and more than 60% of the Maldives' foreign exchange receipts. Over 90% of government tax revenue comes from import duties and tourism-related taxes.