Calculating GDP Using Asp.Net(C#)

I have the following task.

 1) Claculating the current GDP of Countries .

 

GDP means Gross domestic product (GDP) or Gross domestic income (GDI) measures of national income and output .

Plz refer the following link: http://en.wikipedia.org/wiki/Gross_domestic_product

Is there any third party tool or webservice is available to use in .Net. Can any one send me the code or suggestion. 

Thanks
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