Answer: Discount rates are used to determine today's value of money paid or received at some future time.
This calculation is used in the cost-benefit analysis in order to place all economic flows of a project that occur at different points in time into a single year currency so that costs and benefits can be compared.
The rates used are typically around 10%, but try to analyze them with other rates between 5% and 15% to determine if the viability of the project is sensitive to the discount rate. It is defined by World Bank or the government of the country concerned.
<span>The U.S. wanted to avoid going around South America and insure less time for U.S. Naval ships to travel and protect U.S. possessions around the world.</span>