The September 11 attacks have cost the United States some 660 billion dollars so far and significantly reduced global investment, according to an Asia-Pacific forum report released here Wednesday.
"The overall costs of 9/11 to the United States were substantial," the report by Apec's Economic Committee said.
"The research indicates that the costs were approximately 660 billion dollars over four years, or between one and two percent of GDP per year over that period." it said.
The report by the 21-member Asia-Pacific Economic Co-operation (APEC) forum, also showed that the attacks decreased world foreign direct investment flows by up to 0.6 percent.
The 660 billion dollars include 45 billion dollars of direct costs incurred in 2001 from the attacks, 175 billion dollars of indirect costs and 442 billion dollars of security-related costs, the report added.
Indirect costs associated with both security and trade transactions increase as a result of extremist attacks and the increase in transaction costs consequently affects the flows of commodity trade as well as financial capital.
These indirect costs include costs for stepping up security measures, the reduction in the number of tourists and additional expenses for delays in moving cargo through customs, said Lee Kyung-Tae, chair of the economic committee.
"Terrorism variables included in the study decrease world foreign direct investment flows by 0.3 percent-0.6 percent," the report said.
The flow of foreign direct investments is considered one of the most important channels for economic development by most developing economies.
"The risk of possible future terrorist incidents, which may result in huge costs and significant redistribution of economic resources, motivated the need for a better understanding of the economic consequences of terrorism," the paper said.